The Hillary Clinton you think exists is not the one who actually exists. It is entirely possible that Hillary Clinton wasn't thinking about the presidency when she defended her husband, maybe a wife actually loves her husband and doesn't want to see his name get dragged through the mud. Maybe she was personally angered by the attacks on her husband and shot back. Perhaps she actually (here's a thought that will blow you mind) she is devoted to her husband and wants what is best for their relationship. It could be that she had no thoughts of the presidency ten years before she first ran.
But of course we all know that's ridiculous. Hillary Clinton isn't a normal human being. She's an overambitious conniving evil liar. After all, she used emails. It doesn't matter that she didn't run for president until she was 60, it's obvious every move she has made was to prepare for the presidency. Giving millions of children healthcare must have been a political stunt. It's not like a human being would care about other people. It doesn't matter that Trump lies more than her, she's untrustworthy because she is. Any bad thing she said in private about people accusing her husband of things that would be unbelievable to a wife who cares about their husband are SMEAR CAMPAIGNS.
And Trump may have said those things (publicly too) but SMEAR CAMPAIGNS!!1!