Saving people is a really hard task - it won't always work. But what you can do is love them, make them feel special and let them know there's someone who cares about them and that their life is worth living.
This guy gets me. There's a a point in time when you reach a certain age when you just feel like not having plans sounds 100 times better than going out. For me this feeling hit at age 18. And I have no shame in it.