In the great scheme of things, everything within our tiny fraction of time and space loses it's grip on meaning. We must attribute our own meaning that are important to us as individuals. This is actually one of the great discomforts that inspire religions and allow it to spread because it gives people a sense of meaning. It's pretty interesting, when you think about it.
As for the hashtag thing, trolling the fuckers gives them ammo. You don't win through engaging them with violence, no matter how good it may feel to deliver a smackdown. Just make fun of them behind their backs like everyone does, but try to hold the higher ground when/if you engage with them.