It's a pity you feel the way you do. I had a similar situation, only nobody told me, I discovered my husband being fucked myself. Rather than your reaction, I found it a total turn on to see my tall muscular husband being fucked by a geeky looking kid who had a very large cock. I didn't let him know immediately I'd watched him, but told him I'd seen everything two days later. He thought our marriage was over, but through honest talking and some confessing, we sorted out a compromise.
He now has his gay fun (Safe) sometimes with me watching, sometimes not. Whilst I get to have a visit from a young guy I know, two or three times a week when my husband is working. We both get what we want sexually and enjoy each others company, in other ways. Works for us. Hope you get through your difficulties soon. K x
This is why men should never marry. They always lose everything in divorce. Bang em and clang em, boys