Boyfriend with Depression... Help!

hi all. I need advice. my boyfriend has depression and he's going through a really bad spell right now. he doesn't feel like he cares about me or loves me the same, which I'm trying to be very understanding and just be there for him. he sometimes wants to be alone and sometimes not. I dont know how to tell what he needs. I'm hurting really bad from it but I dont want to tell him that. what can I do? he's not attracted to me, doesn't want to talk, or hang out, I'm running out of strength to deal. HELP!