What can I do, hurtful past, hurtful words, strong love, but lately I am lost?

[a.xox]

My boyfriend and I have been together for 4 years and in september I noticed things started to change. I noticed him acting less like the sweetheart I feel in love with. In the past I have treated him pretty badly, everyone has a past but for me I just could not let go of his and I would bring it up every chance I got to rub it in his face. I am the kind of person that if you let me push and push I will see how far I can piss you off. I hate this and I am trying so hard to change. Recently he told me that he cannot do it anymore and we had a big talk and decided to take a break and try to let time heal us. I told him that I was going to change because our relationship is so important to me but he said he cannot do it. Not even 24 hours after he told me this I found out he was texting and flirting with girls that he knows he and I have issues with as part of his past. I poured my heart out to him, begged him almost to give me another try. We still are living together and it has only been about 4 days but I am so upset I keep bringing it up and he does not want to talk about it at all. I feel like he is being distant and rude and trying to prove a point to me about what it feels like. I feelso terrible for how I have acted but it was not just me. He is not perfect. We talk like normal people we just do not show affection. Well he doesnt. I told him I would wiat forever and he told me that we will be able to work it out, but the more it seems I have the need to bring it up (I cant help it!) the more distant he gets. I just need to know if we get through this, will he ever treat me like he did? or will he always be like this? I love him to much to let him go