Unsure how to deal with the behaviour changes please help
My boyfriend and I have been together for 8 months now and we have lived together since the day we met. I am very concerned because over the past 6 months he has changed dramatically at first he was all hugs kisses and cuddles and telling me how much I mean to him and how much he misses and cares about me... then after about the 2 mth mark he slowly became grumpy and now it has progressed into him screaming to the point that he vomits even over the littlest things like putting garlic in the food I am cooking for myself. He has only worked for ~1mth other then that I have been the only one with an occupation. If I ask him about his job search I get yelled at and told that I am a harping him and that the reason his personality has changed is cause all I do is nag. If I ask what he did that day when I get home from work he won't even answer me or he will just say ugh nothing so I have to question him about everything in order to find out what he got up to... I am really beginning to resent him and I don't want to cause when we first got together we had the most perfect relationship and I want those times back. I really don't know what has happened since I have not changed anything. I do everything I can to help make life easy on him and I give him my brand new car (which in 8 months he has put ~15-20 thousand kms on it, yet apparently he does nothing but sit at home all day and goes out to hand out resumes) so that he does not have to take a bus,because he does not have a street legal car. I haven't bought anything for myself since we've met because any of my extra cash goes to hm for clothes, smokes, or anything else he needs. I felt guilty cause I used my extra cash one time to get a budget hair cut and box hair dye. All he ever says is that I am greedy and all I care about is myself and I dwell on my past and I compare him to my past all the time.. I never talk about anything to do with my past or child hood because he just tells me to be quiet cause he does not care about it and doesn't want to hear about it and that if I ask him about his past it is none of my business. He has changed so much to the point that I am not allowed to sit near him while I eat (actually I am hardly ever allowed to sit on the same couch as him), I am not allow to snuggle with him while we are relaxing, watching a show or in bed, I am not allowed to hold his hand practically ever cause he is just not in the mood or he is too hot or my dry hands are apparently all clammy. I just don't know what is going on cause he will be sooo happy then one little thing changes and he goes psychotic punching holes through my walls punching my steering wheel in my car so hard he crumpled the emblem, punching cement walls, basically doing anything he can to get out his anger. I informed him that my very close friend would be coming from quiet someways to spend a weekend with us and because he is another male my boyfriend said that he is not allowed in the house and if he takes one step in our home he will lose it on him. Since he is convinced that he is my ex boyfriend or that I had some form or relationship with him at one point. I ensure him I have not, my mother has also assured him that it is 100% friendship yet he still refuses to believe it. Please can someone help me out so I can get my relationship back on track, since I would rather try and fix it before I just give up and walk out of it.