Why

do political wives put up with it?

They don't necessarily put up with it. But those who do may like the status of being the wife of so-and-so; others, like many wives, find their economic options rather bleak and are afraid to leave; or, believe it or not, there are things in a marriage that are more important than sexual fidelity, and some wives will put up with the cheating as it takes pressure off of them. That doesn't mean they don't care about their husbands or vice versa.

By the way, Bill Clinton ditched Lewinsky during their unconsummated "affair" (the dictionary meaning of affair really got twisted) because he cared about his family, especially Chelsea, but don't expect the media to tell you that. Where he messed up is he didn't tell Hillary when the crap came out in January of 1998. She was humiliated as a result, and he was consigned to the couch for quite some time.