Is my husband pretending to be indifferent to the woman he cheated on me with? Or does he seriously want to...?

If he has not broken all contact with this women, then he is still having at the very least an emotional affair with her. I think you are right by saying he still has feelings for her. I think it is time for him to be totally honest with you about this situation. I have always stated that after you forgive and try to rebuild a marriage that the past should be left in the past, however his past seems to be coming up in the present and it needs to be addressed. I would make him sit down and answer my questions giving truthful answers this time. If you still want your marriage to work, he is going to have to be honest about his relationship with this women in order to move forward. You deserve better than this and if it has been over a year, he has had plenty of time to get over her. It is your responsibility to yourself to let him know that all contact with her is to be over. You need to let him know that you love him and want the marriage to work but you have had enough of this and it will be the last chance you will be giving him to save the marriage. Tell him no more contact with her or you are done with him. Life is too short to play second fiddle to a man that does not respect you enough to keep hurting you over and over again. It is like pouring salt into an open wound. Don't allow him to do this to you.