Most Helpful Girl
First of all, you should not feel worthless because what he is doing says nothing about you, but everything about him.
Second of all, what he is doing is unacceptable. I've recently had a fight with my boyfriend and for the first time ever he ignored me for a bit more than 24 hours. I was devastated – and angry. I told him if he does that again, he doesn't have to come back at all since ignoring a partner is one of the lowest things one can do.
I know it must be hard now. You probably want to keep reaching out to him until you get a reply, ANY reply. But try to remain strong. You ignore him now just like he ignores you. Give him a taste of his own medicine. Don't make him feel like he's the great guy who can act like an utter twat and get away with everything. You show him that you have boundaries, and that you won't just sit there and wait for him to reply when he's done with being an inconsiderate asshole.
He will definitely contact you at some point, but until then, you stay away from him. Don't even look at his things online. Try to have fun and keep your mind busy. I know it's easier said than done. But the worst you can do now is keep sending him messages and keep checking if he's been online or if he has written.