Supporting Someone with Depression

My boyfriend thinks he has depression but won’t go see anyone or do anything. I am the only person that knows. I know what he is going through is terrible but I am getting so exhausted trying to help him. Every weekend he gets drunk and the next day is always so bad. I don’t understand why he doesn’t just stop drinking so much?! It’s really frustrating. I’d never tell him how hard I am finding this but wondering if anyone has tips or is going through similar? I feel mentally and physically drained. It’s so much to carry being the only one who knows, and so much pressure to feel like someone’s life is in your hands.