Jealousy is consuming me. I want out..!?

My boyfriend and i have been together for a year now. it hasnt been easy. I am feeling now that the relationship is hitting a dead end. we fight all the time, he has little respect for how I feel, he leaves the house at wee hours of the night and comes back the next day, no reason given. Anyway here is my problem i like the guy but i know i must save myself the heartache. Problem now is, I cannot reconsile with the tought of having someone else make love to him other than me. That paralizes me. I am having trouble living with the thought that someone will give him more than i have. he is an adorable guy save for when he is drunk, he is the jealous kind. he is 6 years younger than me. We r in our 20s. Please provide some profound advise on how i can claim my life back. It is my problem not his. He is having a good time, i am drowning in pain. What should i do?