I’d try not to overanalyse it myself. He’s with you, remember? And he recognizes your feelings of insecurity at times, says he loves you, and that there isn’t anything to worry about. He obviously has no intention of going anywhere. He chose YOU.
Of course you’d like to see all contact with the OW termined immediately, once and for all. It's only natural. But he seems to want to let her down easy - probably because he feels a lot of guilt towards both of you at this moment. It's probably best not to make an issue out of it right now, and let him work through his own mess. Hang in there. Time is on your side.
