Will he always hate me?

5 months ago my ex told me he wanted to go our seperate ways. I tried very hard to save us but went about it all wrong. He immediately got involved with a 26 year old. (he is 35) They are already expecting a baby. He always told me he didn't want children. He says he is happy and to leave him alone. Well I have found out that the baby may not be his and so I tried to dig deaper to find out for him. He only resents me more. I give up and do not want to be a problem but I don't want him to hate me either. He told me that I will always have a special place in his heart one week and the next he says he hates me. I was with him for 5 years and we were engaged. I thought it was just a phase he was going through. He got her pregnant after only 10 weeks. I really don't think they will last and neither does anyone else including his friends. Actually his friends hate her. She is a tramp. Regardless of their outcome i don't want to be hated by the man who owns my heart. I am going to leave them alone. I am still very hurt by all of the things that have happened so quickly so take it easy on me please. I just don't want to be hated and wanted to know what other peoples opinions are. Do you think he will alwasys hate me if I just leave them alone. I know we will never be together again and I accept that but I hope he wont always hate me. I know I have made some mistakes but this was one of the most hurtful times in my life. I am 42 years old and have never felt more alone and devastated.