My boyfriend makes up things and accuses me of lying constantly. I have grown so tired of having to defend myself, keep telling him to stop and explaining every small thing I do isn't a lie. For example if we are out in public together there are men and women walking around but if I am looking in front of me and there happens to be a man there he will start saying why am i looking at them, when i am not. Or he will say that I'm an attention whore so I'm looking at this person to see if they are checking me out. It is really abnormal. I am only looking in front of me, I am not doing anything but when I say this he will scream and swear. Immediately he gets very nasty and calls me a liar, followed by every swear word under the sun. This is just one example of this behaviour. He will constantly make up things in his mind, which he has decided has happened when it hasn't and decides that I am lying. I just don't understand why he does this to me. I spend everyday being sworn at, accused of lying, any small thing turns into a big fight that lasts hours with every weakness I have been thrown in my face. Then he pretends like he didn't do anything and blames me for it. I just am floored by this. He then gets very angry and aggressive that I am upset by this behaviour and should act loving towards him as soon as he is done picking me apart and screaming at me.
There have been many times where he has done these things in public on the underground where he will say a guy was looking at me and I'm *insert swear words* for not telling him someone was looking at me. But this is ridiculous because I don't see anyone looking at me and again I'm not doing anything. He will say these things on a crowded train and when I tell him to stop, he tells ME to stop making a scene and then starts to loudly shout 'Why do you hit me?'. At that point I start to cry because he was swearing at me and being so nasty and I'm not the one making a scene I just tell him to stop. But he will do this all over the underground, on the platform, on the escalator, on the train. I don't hit him, he has tried to strangle me several times. But he really adamantly says this hasn't happened. When I'm in the car driving and he randomly starts screaming at me for being a whore for flirting with me (which i don't, never have and don't have male friends in my life, don't talk to males at all unless they are family) I try defend myself by saying I haven't because I haven't flirted with anyone. He just tells me that I deserved to get cheated on by my ex boyfriend, I'm an attention whore, liar and insert all possible swear words in every combination. He will do screaming in my face while I'm driving which is dangerous and when I finally can pullover he just lowers the window and screams to people in my neighbourhood that I hit him and why do I do that to him. There is no getting him to stop. His friends keep adding to this by saying they say me with a bunch of men but that's not me they saw! But he chooses to believe them. Somehow because I don't agree with the story he has made up in his head I'm very untrustworthy and a liar, but I'm not like that. He just decided that he was not my first time, but he was! It really hurts that I waited until I was 23 to do that and he just states that I'm lying about that and I had sex before, followed by a convoluted story he made up that I did that with my ex boyfriend and that's why I was so upset after we broke up. But this isn't true and no matter how many times I told him this he would just get angry and very aggressive and say things like 'You'll see what happens for lying to me' in a very aggressive way. Once a day has passed he will act like he never threatened me, grabbed my arm aggressively and proceeds to call me a twisted manipulative liar for saying he did that....but he did! How can he just deny that? I'm not allowed to be upset by that or have space when he acts this way, but if I missed his call once 2 months ago he can just fight with me over it again and again and again, and uses this to deflect the issue that he just threatened me and got very aggressive. Where did they person I have known for so long go? I don't understand anymore. How can someone break me down to this point that I can't seem to walk away and stay away?

I just don't understand why he is doing this to me? Why couldn't he just be happy with me? He is just ruined our relationship by making up stuff and there is no reason for it. He turns everything into a huge fight and tells everyone we know that I don't support him or do anything for him but it's really the other way around. People just believe him. I honestly feel so broken inside from this and I don't know how to get through it. Can anyone even help me?