If he has really ended it with the other woman and is truly sorry and you BOTH commit to repairing the relationship you can and will trust him and have faith in the relationship again. Only with all those things though. There must be complete and total honesty/transparency between. Think of things he can do to help ease and quiet your mind. I asked my husband to let me know BEFORE going certain places bc finding out after the fact made feel like like he was hiding it and made me like fool.... I asked him not to omit details just bc HE didn't think they were important.... I asked that he not have conversations with other people when it requires we make a decision together (he has a real problem telling people he doesn't care or is fine with something but they have to talk to me)... Don't make me ask 20 questions just tell me the whole story the first time I ask...don't respond with anger or irritation when I ask questions...let me know where you're going and when you plan to be back...exchange phone passwords...etc. You'll have you're own list of ways he can help heal the broken trust. Other than that it just takes time and consistency.