Big problems with my bf.

Okay, well I've been with my bf for about a year and a half now, but since Christmas its basically gone all down hill. I've come to the conclusion that we don't actually have a single thing in common, and he doesn't seem to have any of the qualities I long for.. he's a little small-minded, while I'm open to pretty much anything. I love art and fashion, and a lot of things that mean a great deal to me, he just doesn't get. I think he needs someone a little more happy to just 'have someone', but I need intellectual stimulation. We never go anywhere, and when we do see each other, it usually ends in an argument.

I am longing for change, but I don't think I'm going to get it. Hes a very needy person - he has a lot of problems, regarding his family - he is fostered, and two of his siblings have been adopted and he can only see them twice a year. He unfortunately is in regular contact with his parents, who are drug addicts and violent alcoholics. He's a lovely boy, so hes constantly trying to sort out his parents lives, but it just drags him under. He also has a very bad relationship with his foster family.) So I'm really the only person who he has a loving relationship with.

I know it sounds very selfish, but I can't deal with the strain anymore - his problems are making him very unhappy, and I can't bare him taking all this out on me. I was very depressed a while back, and its bringing me back down again. I'm crying practically every night, because I feel like a nag and an awful girlfriend, and we're nowhere near as close as we used to be. He could be so much happier if he just let go of me and found someone else.

I've tried talking to him about his problems, and offering help, but he usually throws it back in my face. He's very stubborn, and seems to attract trouble. He just digs himself into a whole, refusing any help and always blaming others. I try to sort things out, but he doesn't respond well to the slightest criticism, and has very little self-esteem. I'm a bag of emotions as it is, in the midst of my exams, I can't deal with it anymore. Last November, I tried to go on a break with him to sort my head out, but I ended up almost being beaten up in school by a load of scary girls from his year, because I'd hurt him.

I feel completely stuck. I just can't bare to hurt his feelings, and I'm scared of what will happen if I leave him. I'm basically the only person he's close to, but it's too much responsibility for me, when he takes everything out on me. He's very vunerable, and responds very badly when things go wrong.. I had a drunken argument with him a few years ago because he was being suffocatingly over-protective. When I left the house to get some fresh air, he put his fist through a window.

I want him to leave me, but I don't want to hurt him.. and if I did do anything rash, or dumped him myself, I would again have a lot of violent people after me. I really just wish he would find someone else who would really have the patience to stick by him. It would break my heart to see him with another girl, but ultimately its the only way out of this horrible ruin of a relationship.

My mum suggested that the next time he sulks, or takes everything out on me, I should refuse to react, and maybe leave him to be by himself, as he's feeding off my emotional outbursts. Kind of in the way you would leave a toddler to tantrum. She thought I should try it out for a month or so, but I feel so shit right now. He's got me wishing he'd cheat on me tonight, just so I could split up with him without looking like a complete bitch.

Although I don't think I can split up with him now, as I'm just starting my exams and it would be too emotionally draining..

Does anyone have any advice on how to get out of this relationship? I do love him so much, but its been too painful recently. It used to be so much fun, but I don't think we'll ever get back to that again.