My bf is depressed😢.

He keeps telling me that whenever he goes home he feels empty and emotionless. We’ve talked abt it and he doesn’t want to commit suicide or harm himself bc he knows that’s not the answer. He says he only is happy when he’s with me or talking to me or at school and feels rly sad when he’s home. I keep telling him I’m here for him and want to do anything to help but idk what else to say I try and do and say stuff I know will make him laugh and smile but he seems depressed when he’s not with me. And idc what to do I rly like him I’m only 14 ( In February I’ll be 15) he’s 16 and I want to do something to help him. I just don’t know what to say to him I’m not good with advice. I don’t want him to be sad anymore and I’m getting worried I may lose him