Are you planning to try some of the ideas about buying some lingerie and such? I think it might be exciting for him to have you dress a little provocatively and then not approach him at all. Just let his imagination run wild. It is worth a try.
I agree that telling him honestly in a non-threatening manner that his spending so much time in the building that COW lives in, makes you feel uncomfortable might be a good idea. But since my H doesn't even talk to me, I may be all wrong on this.
Everything happens for a reason, maybe Dad needs to find that it isn't better out there, he needs to realize how good he had it here. Maybe he will find God and that is the most important thing when he finds Him he will know he is supposed to come home.
