Lulu excellent story! very much like my DSIS when she met her DH, he held her hair back while she threw up on his car bonnet, first meeting!
I worked in a pub, eleventy million years ago and a regular loner kept asking me to go out for a drink with him, this went on for months. I would reply with trilling laughter and no, I don't go out with customers, until in the end I thought, FFS, just go for a drink and get it over with. So I did. Eek, shudder! Big mistake!!
He spent the whole evening, in a 'rival' pub, saying that all these people were not happy, it was all fake, they were all miserable, they were so wretched 
So get to the end of the 'date' (I hope) and he insists on going to a club! Stupidly I agree and off we went! He was even worse in there! They are all psychopaths, look at them, they aren't happy, it's all a show. Pathetically I just sat there, thinking, please let me just go home. This was about 38 years ago, I was naive.
So we get a taxi and go home, slight frantic fumbling in taxi, much avoiding his mouth and scrambling to get out of taxi, get in house, phew, thank God that is over..............
Oh, no! I am in work three days later, when he comes in and informs me that he has called at my family house, has met my Mum and has left me some records to listen to. ( See, told you I was old!). I used this as an excuse to say, actually I don't appreciate that, I'll return your records, and I don't think we have anything going on for us ='get lost! He looked very hurt but seemed to accept it.
No.........!!!!!!! He would come to the pub every night I was working and just stare at me, from the end of the bar and then one Sunday night he asked to speak to me after work. I warned my boss and asked him to come and rescue me after 10 minutes, then met said sad man in pub car park. Where he confessed his undying love me, told me he had given up his (long time) job as he needed to concentrate on me and he just knew we were meant for each other!!! I was horrified, he gave up his good job, WTF? Luckily the boss arrived and warned him off and even though he cried, I was quite shocked and determined to keep him away from me. I actually met my DH some weeks later but I would often see the 'stalker' around, especially in way out places where I wouldn't have expected to see him.
I did feel guilty though, why did he get so fixated on me, I was polite but never encouraging, but I think my first mistake was actually going out for a drink with him, he saw it as a green light to the future.
I hope he found someone else. Me, and my now DH, moved out of the area many years later and that was it. I stopped seeing this bloke around, I used to find it very unnerving as if I had done something wrong. But I'm sure I didn't.