As much as people like to think that they're a special sort of snowflake, or that suicide is only prevalent in our society, they are dead wrong. Suicide has been going on forever, and honestly if they reach that point where they're so mentally exhausted that they want to end their life, why force them to a life they don't want to live? Why bar them in a 10x8 feet padded cell, so they can face even more pain? If they want to go, they have that right. The life is theirs, as much as people want to pretend that life is a gift, if you're born with a mental illness that deteriorates you to the point that you just want out, how exactly is that sort of life a gift? If someone can look me in the eyes and tell me that a life of pain is a gift, I'd know they're a liar, a filthy liar. It is their RIGHT to end their life, it's their life, everything anyone says is moot, in that regard.
However, on the flip side, we should try to help these people as much as we can, if you're a friend of somebody, you help them try to get back on their feet, reason with them, put yourselves in their shoes, recommend hobbies, hang out with them, support them. Do whatever you can. If in the end, they still choose to commit suicide, that's their decision, but at least you can look yourself in the mirror and know that you truly tried.