Do you have leave your partner during the time he needed you the most?

My bf and I live together for 4.5 years. It's been up and down, and there's more bad times than good times. But there's plenty of love in the relationship but we just couldn't be happy. One of my main issues is that when I think of future, I don't think I can marry him. He is not financially stable, he is unemployed currently and now he is depressed. I think money is the number 1 issue I have with him. He has literally nothing but me. He feels that he's old and has no skill. he has huge gaps on his resume, mainly because he was working for himself for few years. BUt now everything is gone. Please help what do you do if you are in my situation. It sounds bad i know but I can't let my future suffer because of this. I keep telling him to look for jobs but he just doesn't trust himself now, I think it is becuase of depression :( Thank you!

He keeps telling me that he has no reason to live anymore, that he has been unhappy for so long now. I dont know how to handle him anymore. His depression is eating him and making him paralyze. I dont want to leave him because I couldn't imagine him becoming homeless and he'd get hungry or hurt himself. He supported us financially for last he 3 years, he paid for the rent and showed me the world. But I share on food and other expenses whenever I have money. He feels unsupported by me. Mainly because what he does for a living is trading which I don't think we can rely on especially if we have family in the future. So I broke up with him. But before I was able to leave, his trading job got wiped out. Everything he has is gone. Now, I'm trying to stay here and be there for him. But Im running out of patience to wait for him to look for a more stable job. He is 42 and has no good history on resume. I've already told him a year ago, he gotta find something else. Unfortunately, trading is what he loves and what he is interested in the most. Now, that fear I had a year ago just happened. His trading job is gone, wiped out! What do I do????