I'm so sorry you are going through this. My mother-in-law found out her husband had a 10 year affair with another woman. She was a wreck of course but she made up her mind that she loved him, wanted him back and forgave him.

I don't know if they went to couples counseling or anything but I definitely agree with the previous posts that counseling maybe for you individually and together as a couple will help you get through this hurdle and help you make a decision one way or another.

If you do love him, which from your post you do, and can forgive him at some point I think it's worth it to work on the relationship. Divorce is horrible. I went through a horrible divorce and custody battle and it isn't fun at all. Since you have a child, you will continue to have constant contact with your husband if you do go the divorce route so you will have a realtionship with him forever so ending it won't complete cut the ties if that's what you are feeling you want to do.