It may be a solution but don't call it a cure. I suffer from depression, and having an understanding of how it comes in waves allows me to know, though at set times it gets worse, it also gets better. I can drink, and smoke, and game, and waste away when I'm actually depressed as a way of ignoring it and essentially killing myself, and then repair friendships and respect during high times. It's a solution not a cure though.
For all the bullshit reddit likes to give SSRIs (like they're government made brave new SOMA) they helped me from just the month I chose to take em, in showing me mental radio silence. The kind of thing most kill their brain hoping to achieve, sometimes causing the opposite. It allowed me to feel not like I was dumb, but like I wasn't some prodigy expected to live up to expectations, like I was normal and capable of just doing something without thinking why. Another solution, not a cure.
Sometimes all it takes is connecting with someone whether new or old, sometimes an exposure to something that sparks intrigue, from hobbies to husbands. Sometimes it takes something that can feel more strenuous than death, like leaving behind a family and identity to become something you "know" is hated. All solutions, not cures.
The thing is depending on the person, there can be any number of solutions, without there ever being a cure. Some solutions work once, some a lifetime. The reason suicide happens is because of imbalance, not just mental imbalance, but an imbalance of reasoning, of experience, of exposure. The problem arises when they're only exposed to so much of the same enmiserating stuff, without having a chance to grasp a different perception. They can see one option left, cause it's the only one they're capable of seeing. Being able to find a different solution to the same problem, sometimes that's the only cure. It's one of the things churches do, and do well. Free community support, a route for finding different solutions (ask god, ask your preacher, ask your church), and an answer to existential crisis. For atheists, an exposure to new philosophies can achieve the same, stoicism and absurdism have done much to improve my internal reasonings, even when faced with how meaningless it is to feel good and laugh and enjoy a good day when I do, if it means I feel bad later. (notso-simple trick, teach yourself to find the bad mood as meaningless as the bad mood has taught you to find the good)