Sweet revenge

But you can't block someone on most social media if they already blocked you, right?

I don't know about Facebook, but every other site I'm aware of you can.

People get cheated on. It's a thing that happens. Yes it's shitty, but she should be able to move on and not harass him.

Wth? So you can excuse cheating with "it happens" as if you just randomly slip and your dick accidentally slides into a vagina, whoopsie fucking daisy, but when someone does a mild inconvenience as revenge for the heartbreak they should just deal with it and move on? No way I'm cool with that. Seriously, sorry for the ranting and anger but cheating is one of the few things I'm just absolutely not cool with.

I'm not excusing it. Of course you should get angry when people cheat. It's a shitty thing to do and they obviously need to be dumped. But they didn't murder someone, they didn't date you just to rob you blind. You will ( usually ) get over heartbreak and you can find another relationship to be in with someone who isn't a piece of shit.
Also, if your heart is broken just get over it instead of being a bitch for revenge. If it lasts a couple weeks it's understandable but if you prolong if you're only going to A) prolong your heartbreak by keeping that person on your mind B) probably get reported for harassment C) no one is gonna wanna date your ass if you reply to heartbreak with revenge

No, I'm absolutely for moving on as it's better for your mental health, but hey, he's had his fun while cheating, I say let her have her fun with some of that sweet, sweet revenge. I mean she's obviously gonna get bored and leave him alone sooner or later.