Desperate for advice, should i stay or leave him ?

Well, i'm only 16 and me and my boyfriend have been together for about 10 months. I don't live with him, i still live with my mother at home. Our entire relationship has been made up of fighting, not resolving, and pretending that everything is fine. He has only ever taken me out once, and has ever only bough me either smokes, or just fast food. He has left me twice for no real reason, he threatens any guy that looks or speaks to me, doesn't let me be with my friends, has threatened to leave me if i were to hang around them, he has hit me, and actually punched a hole in my mothers wall. He doesn't have a job, he has anger problems and has recently been put on anti depressants *sigh* which has been very stressful because he thinks i am the person that has to help him, and fix him. Basically he is selfish and completely careless for my needs. But now, i am pregnant with a baby boy, so i can't cut him out of my life anymore. I'm extremely tired of waiting for him to change, and i wonder if he even will ?
Basically, does anyone think he is worth the trouble or should i just get out while i can ?