Complicated relationship

i had crush in my 11th class. Suprisingly in 12th the same guy proposed me. From then we were in relation for 4years. To be specific in long distance relationship. he always told me that his childhood wasn't good and he is a bad guy. because of me he turned to a good one. i was happy. but he did many things that would hurt me. i forgiven him because he loves me so much. Am not too pretty. His only problem with me was i should try to dress up and make up well to look beautiful. because of that i never asked him anything. At present because of career stress he is breaking up with me.He asking me to leave him because he is afraid that he might cheat me later.and also he says that he is not interested in any other girl.I dont know whether he is cheating me or doing all this wantedly out of stress.he wants to take a gap in relation and do all the bad things he wants to do and return to me. should i leave him or stay with him??? P.S.: i love him so much and I can't imagine my life without him. and I am ready to be with him if he returns to me.