OH does not really care about fault and it can be quite costly in attorney fees to go that route.
As stated above, I have similarities with OP in my divorce case. My ex committed adultery and although this was not brought up as fault, I do think it helped my case. I came out ahead, and much further ahead, than I would have, if I been stupid enough to sign the dissolution papers ex had all worked out and handed me the day he left. He was so smug, thought he had it all worked out. It was so to his advantage and was a pathetic attempt at trickery IMO.
I tossed them to the floor and told him I was not signing a thing. I believe that was his first inkling that it just might not be as easy as he thought it would be.
"Don't cry because it's over, smile because it happened".