Not even that, I think. While I'm not a cheater (honest, I swer on me Mum), IME women can usually understand if it's another woman, but are completely wrecked when it's a man. They just can't comprehend it. Vice versa for men - examples from my circles: "he must have had a bigger dick/a better car/more money" - whatever. Those are understandable to an extent. They, even those who find a theoretical threesome with a pair of lesbians so very ungh fucking hot, man just fail to understand when they're being cheated on with another woman.
I suspect Jimmy's wife would have been relatively fine with Jimmy either trooning out or cooming out of the closet as bisexual. Both of these, however, especially considering the poor woman's ongoing health crisis, she just couldn't handle and noped out fast.