Depression and loneliness. To do now?

There's a guy I've been talking to from few days. He is nice but he has a past.he  told me about his problems few nights back and how he loves darkness. He feels like he's gonna be prisoner to this thing forever. I automatically felt a connection the day we first talked and 2 days back he told me everything about his life. It's terrible what all happened to him. I just feel so attached to him like even though he lives in another country I just want to make him come out of all this bc I'm really concerned. He says that he is a bad luck and warned me to not to fall for him because he might end up breaking my heart because now he don't let anyone in but then why the hell he told me EVERYTHING!  as normally guys don't tell. He says that he has different personalities as in one day he is going to be very caring and the other day he's gonna ignorant and I really thought it wouldn't be difficult for me to handle it but now it is. I just really do care. What am I supposed to do now?