Best way to defend Trump is to:
1) Say "What sentence or statement did he say that upset you?" Now if they can't think of one or say "He's anything ending in -ist or -ic" or "EVERYTHING!" Don't argue with them, their clearly not looking for a meaningful discussion, they just want to bash you with their perceived moral superiority.
2) When they say something beyond hyperbolic such as "He's gonna start a nuclear war" or "He's going to remove LGBT rights" tell them to play it out (meaning ask them to explain how he will do this.) And when they do play it out, they realise how unfathomable their imaginary world is.
3) If they bring up the bus conversation , just say "Women are attracted to fame and success, and when he said you can grab them by the P**** he meant it is insane what these women let you get away with"
There is actual criticism of Trump i.e too soft on russia,tariffs on businesses who want to leave the US , not a true conservative and is changing the how the republican party works.