To put it simply, Jon needs to step up and deal with this. It was easy for him to turn a blind eye before, but he's seen it now and you've called out the behaviour so he's aware its a problem to you. He also should have put her straight when she was being unkind at the dinner you hosted - she went on about an orgy and hand fed him?!?!

I have a feeling he's not going to do much about it.

Hi, I am sorry this has happened to you. I have had a similar experience and thought maybe it might help if I share it with you.

My husband at the time (now divorcing) became quite obsessed with me having sex with another man - I don't believe it was a fetish, more something he wanted to do and then have me (his wife) come back to him again. It got to the point where he called a friend of mine to arrange it (luckily my friend didnt pick up the phone). He also said if I didn't choose someone then he would pick for me and I later found out that he had started arrangements with a guy from his work. He was also showing sexual images of me etc.

Im pretty easy going with most things and possibly would have gone along with it under different circumstances but he became so focused and obsessed with it that I went the opposite way completely.

Another thing he did was during any intercourse he would talk to me constantly about other men and women (im bisexual) and there was a couple of particular sex acts that he became very focused on even though i asked him to stop doing them because I didn't like them.

These things went on for years, I was deeply unhappy.

No one here can tell you what to do but from my own experience, your husband wont change, he will only get worse just like my ex did. Protect and support yourself because he's not going to do that for you.

Note that he is now my ex.

It means they are most likely into kink and that's ok. Don't laugh at him or shame him, just move on and forget you saw anything.