Hilary got some people excited. Obviously not enough, but to some pockets of the Democratic coalition (2nd wave feminists, certain subsets of the gay community) she was a rockstar. I was in rooms where I saw excited and passionate support for Hilary, and it wasn't all about hating Donnie.
-Al Gore won an Oscar, a Nobel Prize, and became a leading advocate for fighting climate change
-John Kerry went back to being a Senator and eventually Secretary of State
So what should Hilary do? Hilary has for the first time in her whole adult life been left without anything to do, politically (presuming that running for office is a gig). I don't expect her to go away exactly, and perhaps she shouldn't. She can shake the money trees that those patrician folks like her grow out of, or she can represent the party to her most vociferous backers. She does have a role to play, I would imagine that she's eager to play it.