Man they are going to have the most awkward "so how did you meet" story.

"keeping it in the family" boss level unlocked.

Now that's what I call a sticky situation!

If she’s 22 and consented without coercion(which is a very open question in a situation like this), and it didn’t start till she was 18, then as alimony and skeezy as it seems it’s probably not illegal per se, but man that’s 100% creepy slimeball on his part. It also depends on how long you’ve lived together. I guess the only good news is if he spent all that money on the affair you can probably get it back via favorable financial settlements as part of the divorce when you drop his creepy ass.

Is your husband Woody Allen?

Seems like the plot of a bad porno

I'm very sorry, OP. You didnt deserve that

It is still an incest.

Cut your losses and run away.

This might be a good time to find a social worker and ask for help. If nothing else, finding a therapist will help you.