i am "manipulative", "cruel", a "liar" and i "lack empathy"

[Artemiss]

Hello. DF changes from Jekill to Hyde and i have serious doubts about marrying him. I spent the last few months being confused, depressed , feeling guilty , doubting myself and my sanity, i even started thinking that i am all that he says that i am. But no one else ever had this opinion about me, the opposite. And if i am that bad why he stays with me? It doesnt make sense. He is thinking that he is some sort of martyr that he puts up with my crap because he loves me that much and i did believe that for long time.
The one side of him is the mr nice guy. He will be sweet , caring and say all the right things, how he loves me, how amazing i am ,how i always being there to support him, he wants me always by his side etc etc
And then is the other side. He gets overly angry over nothing, The little small tiny unimportant things will send him into rage. If i dare to complaint about something he starts braking things or going away to cool off. The problem is that i dont even manage to say one sentence before he reacts like this. Example yesterday i answered his call 3 minutes after he called. He said that i was too late and i should be there the time we agreed. I told him that this doesnt make sense and its just 3 minutes. He got so angry that he had to "cool off" Then started sending messages in capital letters "so i understand" telling me that i am ungrateful and nothing pleases me and that he is certain that i cause problems because i have a plan and probably i have another man here and i want his baby(?????). Then demanded an apology . And this is his mentality and behavior when he gets into this mood.Other times i can say half a sentense and he starts smashing things, usually when we are on phone but i can hear him. He blames me for everything and when i say that he is responsible for his own behavior he replies that i make him do it or that women arent to be trusted because their mentality changes with their moods
He also claims that i am a liar. Every time i have different opinion apparently i am a liar.
I am sure now that there is something wrong with him and not me but i would like some perspective please. When he is nice he is very nice and he claims that i change him and if i can only be nice he will go back to normal.By nice he means to say always yes and always agree with him

That's very nice of you to say!

I think I'm working from a 'expect the best, prepare for the worst' perspective.

There is still sometimes an emotional hangover from him where I hear him in my head saying the things he used to say 'that didn't happen' 'you are crazy' 'I'm a great boyfriend' 'you are overreacting' 'I'm sick of these dramatic tantrums' but it is significantly reduced.

I totally agree with Emma really as I know there is a massive risk of falling into a black hole of obsessively thinking about who he is and why he is which would keep me stuck.

And whilst when someone asks 'what are you afraid of?' You feel ok answering with something like 'I'm afraid he'll be physically violent' when you are with someone who tortures you mentally it feels ridiculous to reply 'I'm afraid that he'll get upset/angry'

In fact it's more accurate to say what you are afraid of is that he is going to completely emotionally destroy you because actually that's what this kind of person does rather than being upset/angry.

OP your 'D'P is projecting all his negative thoughts about himself on you.
He is the one who is manipulative, cruel, a liar and lacking empathy! Amongst other things!

You are suppose to be marrying your best friend who you can Always rely on, who'll always support you, who cares deeply and who'd never want to be the cause of your pain.
Your Partner can't even show any of the above before marriage. A legal document won't change him to who you wish he could be, he's more likely to ramp up his rages.
He wants complete control of your time and your brainspace. You are his object to use n abuse!

If you marry him his behaviour will escalate very quickly. Almost certainly to physical violence at some point.
Mind fucking will continue so you don't know whether you're coming or going.
Nothing that you do will ever be right and you will be blamed for all that is wrong.
Flipping from nice to nasty over the slightest thing.
I lived through this nightmare and just about got out in one piece after various beatings, being thrown down concrete steps and he said I imagined it all and none of it happened.

It turned out that his family knew that he had diagnosed mental health problems and decided not to tell me.