I would look at the whole situation and sit down and discuss how yu both truly feel about each other. Being it was his ex apparently he must have some feelings that he has never left go and he needs to decide if he wants to be in a relationship with you or the ex. Its a hard thing when someone is cheating to decide why they do what they do. It also can be that he went back to her for some type of comfort that she had given to him that he doesnt ahve in your relationship, which doesnt mean your doing anything wrong its just something that he felt a need for again. I would defitely talk things over with him and decide where both of your feeling are. If he is truly sorry and wants to work things out with you I would say give him the benefit of the doubt as people are humans and tend to make mistakes, but only if they are truly sorri and depending on the circumstances would I take that into donsideration. If this guy is living with you to keep him then I would kick him to the curb, otherwise get an explanation and discuss things and decide what would be best for you and how it will effect you in the future with this guy. They usually say once a cheater always a cheater especially going back to an ex. So take all things into consideration and make things work for you, if you are hurting think of the whole situation and think about if he would do it to you again. Lots of luck. Cheating is terrible its a shame when people go that resort for any reason.

That is quite the betrayal of trust for you. Seems he did not cheat once, but you mean just one other female? The forgiveness is entirely up to you.

Why would you want to be with a cheater? I think you should find someone new and tell him to do the same Because he cannot be trusted. A leopard cannot change his spot.

First of all he was your friend for 4 years and he still didn't respect you enough to be faithful. If he isn't capable of being faithful to someone who he has known as a friend for so long, who knows what this man is capable of. I'd run like the wind. Not to mention it's his ex wife that he's dealing with. Sounds like he's got way too much baggage. You deserve much better. Don't let him have his cake and eat it to. Find yourself a real man!

Sometimes relationships can be salvaged, it simply depends on the level of commitment you are both willing to give to the repair.

Not only did he disrespect the commitment that you guys made in moving together, but he LIED! Move on

If you really love him forgive him and give him another chance to prove that he loves you and will not cheat on you.