I think the word 'fight' is a bit misleading. People don't perceive themselves to be 'fighting' when they either accept or forgive bad behaviour.
Looking at my friend's marriages or long-term partnerships (not counting prior to that), I would say most have accepted or forgiven potentially marriage ending stuff, such as terrible cheating, snogging someone else, alcoholism, even though each one of them would have declared they never would.
Women often don't leave in the face of considerable provocation, and I get why- kids, money, status quo.
Very very few, if they have suspicions of interest in another woman, honestly just say 'bye then'.
Some women then leave years later, so there's a lag time IMO. But my friends appear to be sitting it out with many awful things behind them, so no, I don't think they 'fight', they tend to try to do what they perceive is best for the whole family unit and what they can face doing at any given time.