My bf is depressed and it’s making me miserable - should I leave him?

We haven’t been together long, but over the past month or so he’s gone back to what he was like a few years ago before I knew him. He lost his job and is stressed about money, all his friends are leaving for uni soon etc. I know he’s got a lot going on and that this is just a rough patch, so I’ve stayed with him even though I can’t remember being this miserable in years. I really care about him and have a lot of hope that things are gonna go back to the way they were at the start of the relationship. I’d feel too guilty if I did leave him, but even though he said he really appreciates me sticking by him, he doesn’t act like he appreciates me at all. He never seems to care when he annoys or upsets me, just gets annoyed at me.

I feel really lost, and things aren’t easy for me at the moment either as I’ve got my own stuff going on. I guess I’m hoping for some sort of advice or anybody else’s experiences?