I am so sorry how hard this must be. Was it clear to him that there is a chance if OW is gone and he seriously works to regain your trust? I read that you just told him you were done and had no hope and wanted to move on.
Did I miss it, the sign you gave him of possibility if he were to work for you?
Mid 30's Psych-abusive M with violent tantrums from XH D 9/15; NC forever on