I seen another guy while my husband and I were seperated...?

My husband and I have been together for 6 years, we are 24 years old, we got married right out of highschool. We have a 3 and a 1 year old, both girls. I love him with all my heart I really do. He started coming home late, not telling me what he was doing all the time, telling me he was working on cars to hang out with friends, he was talking to this girl we went to school with in a way he should not have, and he was calling me names. I am not innocent I called names back and was a ***** to him during this time. Yes many times I took him for granted when he would get me something for vday or our anniversary I would either get him just a card or nothing at all. He has called me a retarded spoiled rotten ***** more times then I could begin to count. And he was emailing that girl things like sing to me and I'd gladely go deaf, I'm claiming your son, you're beautiful inside and out, I dream of being there with you and your son, I wake up in the morning expecting to see you and say good morning beautiful but its not you, etc. So when we seperated I moved out with a friend and her husband. They had a friend over a bit and he started talking to me, it cheered me up. After another big fight with my husband over the phone I had a bit to drink, alot to be honest, and I messed around with the guy. I didnt think I would ever get back with my husband. And I felt horrible and I still do. When we did get back together I lied and said I never did anything, I was so happy to get him back that I thought that would ruin it. I just wanted my family back, I know its wrong to lie. This was 9 months ago. My friend I lived with told him that I slept around on him, that is not true. And now my husband thinks and is telling everyone that I sleep around on him. I can't disprove it and he wont believe me. My dad had an actual affair with my step mom and they were able to work things out and are better then before. I am hoping that will happen for me. This was brought up 3 days ago and he wont tell me if we are going to work things out or not. I keep asking and he said 'Did I kick you out of the house and ask for my ring back?" but then he will say he will think about it and decide one way or another on his own time. The next minute he's saying I ruined the whole last 6 years of his life and that I want what I can't have. I don't know if him saying those things are just because of how hurt he is or if there is no chance. I dont know if I need to just stop talking to him all together til he comes to me or what to do. I am so sorry, I feel empty and sick inside. I don't know how to make this better. I know I was wrong and I am horribly sorry. He swears he never cheated on me, or messed around when we were seperated, he swears what he said to that girl was just innocent friend talk. I know this is wrong, what I did, and as much as I agree it was wrong and immoral, I just don't feel it was literally actually 'cheating' I know it was not right but I just don't feel like this is something to divorce over, it was when we were seperated all those things were going on it was just that one time, I've never talked to him again I even forgot his name til my husband told me today. This was almost a year ago...