Jo, I think you should let him know that you know and how hurt you are because of it. I think perhaps a letter or email would be the easiest. It gives you time to think and get your feelings out there. Perhaps you should read James Dobson's Tough Love book and get some ideas. It teaches tough love without burning bridges. I read the book a long time ago. I just with I had been strong enough to implement his ideas, I think I would have closure one way or the other right now.
Hugs
Life's challenges are not supposed to paralyze you, they're supposed to help you discover who you are. -- Bernice Johnson Reagon