"So that would be unlike Morning Joe, where adultery led to two divorces."

1) Scarborough was divorced long before their escapades.
2) Not a fan of what has occurred, but at least it was consensual between the two of them....unlike the harassment taking place at Fox News.

"Can we stop pretending that sexual morals are based on liberal or conservative ideology?"

I agree, except you're forgetting something.  Back in the 1990s and early 2000s, the GOP liked to paint themselves as the party of morals, family values, and anti-LGBT attitudes.  Therefore, when Republicans/conservatives like Rush Limbaugh (3 marriages/drugs), Mark Sanford (extra-marital affair), Larry Craig (gay sex in airport), Mark Foley (hitting on male pages), or Eric Bolling (d* pics) is found to have participated in less than moral behavior, they're going to get hammered for it.....perhaps more than a liberal will.....and rightfully so.