This is an essay diatribe post I once made on the Buffy boards in response to the question 'Did Angel love Buffy?' (N.B- Bangelfans are crazy there) Sorry for length (I've had to split it in two!)
TLDR: No he didn't.
Chronologically (from what we know from the whole of the 8 seasons of t.v shows (I've never read the comics and cannot class anything where Spike has some kind of space ship as canon) not the order we learn it):
Liam is a selfish, lazy, drunken waste of space who has never been in love but often sweet talks women into bed before abandoning them the next morning ( The Prodigal). He is 26 years old. He stumbles into an alleyway where he inadvertently gets turned into a vampire and becomes the worst vampire that ever walked the earth (even the master calls him 'the most vicious creature I ever knew') and, even though plenty of other vampires are capable of deep and abiding love (Spike and Dru, James and Elizabeth), Angelus - for some reason - is not (Dear Boy).
Then he gets his soul back. He tries to stick with Darla but that doesn't work out (Darla) and so heads to the U.S and spends the bulk of the twentieth century completely alone (Angel). His soul is still pretty new, at this point, he's drawn to doing good deeds - but then being around people is too tempting and painful and he has to push them away (the puppy rescue in Orpheus). By the 40s he has separated himself completely and cut himself off - not helping and not being around humans (why we fight). He's still in this mode in the early 50s, living in the Hyperion, but here he makes his first human connection. Against his will, against his better judgement, he starts to help Judy and she draws him in. He starts to think he has found a friend - he doesn't want to eat her, he is just enjoying having someone to care about and having someone care about him. Which is why it really stings when she turns round and betrays him (Are you Now or Have You Ever Been).
So, having been burned the one time he tried to reach out and connect to someone - he then goes back to avoiding all people. He goes to Elvis' wedding and a few Barry Manilow concerts, has a few drinks with the Ratpack ... but he doesn't connect and he doesn't help. Then comes the night of the armed robbery in the diner - he doesn't ring an ambulance and instead feeds of the cashier. And his guilt comes back in full force - as bad as it was when he was first cursed. He spends the next twenty years homeless and starving as penance - he is at his lowest ebb ... and this is when he first meets Buffy (Becoming)
In Helpless he tells her the story of how he watched her come out of school and walk down the steps and he loved her, because he could see her heart. Except - he couldn't and he didn't - that's just not possible. He starts off his relationship with Buffy by stalking her from a distance. He watches a 15 year old child (bearing in mind he is over 200 and even without that was 26 when he was sired - so...) she's sucking on a lollipop for god's sake. He knows nothing about her (other than she likes lollies) what he sees is the innocence and purity of her youth (doesn't hurt that she happens to be very beautiful as well). She's being called as the slayer - the one girl in all the world to stand against the darkness - so he can infer from that she must be morally pure, as well. Buffy walks down those steps and what Angel sees is someone who is truly good (though he can't possible know that to be fact, it is simply an impression that he is projecting on to her). He 'falls in love' with her perceived goodness - and more than that, he is given hope that if someone who is wholly good can love him back then he is a thing worth saving, he can be redeemed (and remember this is happening at his lowest ebb). He falls in love with the idea of his own redemption - and (in this moment) he ties that up with the person of Buffy.
Angel is not a romantic - though. He is an obsessive. He never loved when he was alive. He never loved Darla as Angelus - though other vampires can and do fall in love. He stayed with her for over 100 years - there was lust and obsession. He was obsessed with Drusilla - but he never loved her. There were other girls he obsessed over and stalked too, one of whom's puppy he nailed to something (Bewitched, Bothered and Bewildered). This isn't to say Angel can't love and he can't be romantic - of course he can, but it is not the driving force of his personality - it is not an integral part of him. It is not what motivates him. Obsession is what motivates him.
So, he goes to Sunnydale to wait for Buffy. It's not clear precisely how long there is between Buffy being called and her arriving in Sunnydale - but it's anywhere between a few months and a year. It's a lengthy period of time in which he sets himself up in a home, gets cleaned up - and then has nothing to do but wait for his golden haired redemption to turn up and save him. The man loves to brood - that's a lot of alone time building up images and ideas that don't necessarily bear any relation to reality - but obsessives don't care about that.
Buffy arrives in Sunny D and, they don't ever really bring this up, but he must do some pretty hardcore stalking of her before he meets her in the alley. He knows she's in town - he must know at least roughly where she lives, as he follows her on her way to the Bronze and he knows she'll be going there that night. (in What's My Line he knows about career week because 'he lurks' - perhaps he is already lurking around her school in the pilot, he has at least lurked long enough to know that schoolkids go to The Bronze, even if it's just a lucky guess that Buffy specifically will be there). This isn't a chance meeting and it is a meeting he has had perhaps as long as a year to plan. His chosen method of meeting her is to stalk her down a dark alley. Practically his first words are to lie to her 'truth is I thought you'd be taller, or bigger muscles and all that'. No - he's seen her before, he knew what she looked like, he saw her getting called - he chooses to pretend that this is the first time he has seen her and he was expecting something different, when it isn't and he wasn't. He doesn't tell her his name. He tells her she has to be ready for the Harvest - but gives her no details as to what that is. He doesn't tell her where she can find the vampires even though he knows. He gives her a gift and then walks off into the dark, leaving her all wrong footed by saying 'I didn't say I was your friend' - he has to get the last word in, has to leave her feeling that he is the one with the power. He has had months to plan this. This is not a chance encounter. It's not that he get's caught short and doesn't know what to say. He follows her - gives her a gift - says the word 'harvest' and walks off leaving her feeling silly. That was a deliberate choice he made. He could have told her what the harvest was and saved her a lot of time and effort. If he actually wants to help - isn't that what he should do? He doesn't, he chooses not to. Instead he acts cryptic and mysterious and quite a lot like the way we later see Angelus play mind games . Why? Maybe because, having had a year to decide how best to meet the girl he 'loved from the moment she walked down the steps' he decided mysterious, cryptic guy was more likely to turn a naive, young girl's head than earnest, helpful guy. He leaves her wanting more. That's it for their interactions in episode 1.
In episode 2 they have a brief conversation in the mausoleum in which he actually negs her ('I knew you'd figure it out sooner or later, actually, I thought it was gonna be a little sooner). Angel is apparently quite the PUA. He could have given her this information last night - but instead he thought he'd rather be a bit of a jerk about it in the morning (and no that isn't because he didn't know she would need to go to the mausoleum when they spoke the previous night - he doesn't know they have Jesse until she tells him. He just knew she would come - and he is waiting for her).He tells her his name and that the vampires don't like him and that's pretty much it.
He isn't in episode 3.
In episode 4 he decides to go for another cryptic warning 'he's coming, don't let him corner you. Don't give him a moments mercy - he'll rip your throat out.' Instead of the much more helpful 'there's a vampire with a big fork for a hand who hunts in Weatherly park - be careful when you hunt him, he nearly shredded a homeless guy last night.' He also gives her another gift (I don't want to say Angel is grooming her but ... if the cap fits.) They have another very brief conversation right at the end in which she tries to find out some basic information and he refuses to give a straight answer (sorry - did the PTB send him there to help her, or play mind games?) As he walks off she says 'oh boy' - clearly the mystery guy act is reeling her in, as well a 200 year old serial stalker would know it would. And that's how Angel is acting - not as a romantic hero, because he isn't a romantic - he doesn't know how to do that. He knows how to stalk and how to obsess.
In episode 5 he comes to give her another warning and then gets jealous that she's on a date. Considering they have had precisely 4 conversations at this point, none of which have gone above 30 secs in length, he's skating on pretty thin ice there.
He isn't in episode 6.
And then episode 7 - we learn the truth and get the pronouncements of love. Now - I buy that Buffy could believe she was in love (not that she is - but that she believes it) She's only 16, he's mysterious and older and handsome. She has all these fantasies about him and to her youth and inexperience that qualifies as love. The fact that they have had 5 very short conversations and she knows nothing about him and he knows nothing about her so they can't possibly love each other passes her by completely. As well it might - she is a child. But if Angel - a man who was a fully grown adult when he died and has since lived over 200 years - seen the world and experienced pretty much everything in it- thinks he's in love with a girl he knows next to nothing about, then that is because he does not know the difference between obsession and love. If he is in love, then he is in love with an image of her that he created himself, and what that represents (his redemption) and not with Buffy herself.
They then don't see each other at all until episode 12. They spend no one on one time together even in this episode. After she has her break down and walks out, vowing to quit, he does nothing to check on her - preferring instead to brood alone. Nor does he do anything to try and countermand the prophecy - like insist on going in her place, like Giles. He sits and sulks until Xander turns up and makes him show him where the vampires are. Angel says to her, in the library 'You think I want anything to happen to you? Do you think I could stand it?' but it is Xander and Giles who prove their love for Buffy in this episode by actively taking steps to prevent anything from happening to her - not Angel. And why wouldn't it be? Unlike Angel they have both spent masses of time with her and got to know her as a person - they can honestly claim to love her for who she is. At the end they all go to the dance in a large group... and then Buffy leaves town for THREE MONTHS.
THREE MONTHS LATER - following no contact, Buffy wakes up to find Edward Cullen Angel in her room whilst she sleeps (because obsessive, not romantic). She gives him the brush off because she has PTSD. He fails to understand that she has PTSD and instead worries its something he has done - because he doesn't actually know anything about her and all that introspection is apparently making him a little self involved. They then proceed to dance around whether or not they should date until the end of episode 5, this involves arguments, melodramatic statements, him gripping her rather violently by the shoulders and snarling in her face about fairy tales and the implication that she is too young to know what she wants (which is arguably true - but if he believes that of her, then he has no business feeling like he might want to date her.)
They have their first official date on Halloween. In this episode Angel actually proves how much he doesn't understand Buffy or respect the person she wants to be and he doesn't listen to what she is telling him through her words and actions. Buffy cuts out on their first attempt at a date because she turns up late with straw in her hair, due to slaying, and Cordelia is already there with Angel, embracing personal hygiene. She says to him 'dates are things normal girls have. Girls who have time to think about nail polish and facials. You know what I think about? Ambush tactics, beheading ... not exactly the stuff dreams are made of.' She chooses to dress up as the girliest girl she can possibly be ... that is the normal that she wants to be. That is the normal that she was before she was the slayer (she reiterates this in Helpless when she compares her former self to Spordelia). But instead of accepting this facet of her personality - that she is feminine and likes the accoutrements of femininity and wishes she had more time for it, he asks her why she thinks he'd like her more that way and goes on to say how much he hates women like that (like Cordelia) he calls them 'simpering morons'. He's not interested in who Buffy is or wants to be - he isn't interested in that side of her. And, counter to what he tells her in Helpless - by his own admission here, he would NOT have loved her if she hadn't been the slayer. He's interested in the hero who can redeem him. Not the teenage girl.
To his credit, he does start to make a bit of an effort. In What's my line he takes her ice skating ... but he's known her almost a year, he claims to be in love with her, he is her boyfriend - and he only now finds out that she likes to skate? He does not know Buffy. He knows the slayer.