The strong and weak nuclear forces are probably keeping you together better than gravity does, those are a lot stronger on small scales.
Larger objects, like planets, stars, natural satellites, etc, rely on gravity to keep themselves together.
But if the value for Dark Energy is large enough (and we don't know its exact value) then, eventually, someday, the universe expansion will rip apart things held together by gravity. And eventually, even molecular bonds will separate, and atoms themselves will be ripped apart.
It's just one possible fate of the Universe... they call it the Big Rip, and between that or Heat Death, you have a very dismal very distant future.
If Dark Energy is not strong enough, or if there is more mass in the universe than initially estimated, then perhaps a A Big Crunch will occur, in which gravity wins, and all the matter in the universe will fall back into itself.