This is a sticky situation. The only thing I will say is that he can't justify his contact with that girl because you cheated. If you agreed to work it out than he needs to forgive you and move with you forward- not justify his behavior because you cheated so that gives him a pass on considering your feelings. I wouldn't back down, you aren't wrong. He either needs to stop talking to her or you both need to consider ending the relationship in my opinion. The only thing that's going to come out of this in it's current circumstance is the same unhealthy pattern of both of you betraying trust. Just how I see it. I do hope it works out though!

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