What should i do about my ex !!!!!!?

i was seedng this guy an he was my first we were to gather for a year and while we were to gather he was still with his baby mamma i didnt know that he treat me like crap he made me feel really no welcomed at his house well i stoped talking to jim i left him alone well him and his baby mamma broke up and he came looking for me left his number i called him and he wanted me to come and see him well i didnt go and see him i was seeing some one else any ways its been two years and we have started talking again and he told me that the reason he treated me like he did is because he was with his baby mamma well he said he was emotinally attatched to me and appolize for the way he treated me he and that he wanted me to be his girl well its hard to trust him and i dont know what to do should i give him another chance or should i let it be help plz