Listening and - as far as possible - understanding.
As Senoufou says, the first step is accepting the problem exists. While those round you aren't aware that their problems are within themselves, nothing can help them, and if you try, you will wear yourself down, and achieve nothing; although it is hard to see those close to you hurting themslves. And by trying to discuss the problems you saw, you did the right thing.
Look after yourself first. Then, if circumstances change you may be in a position to offer help. But if you wear yourself out, you will be no use even to yourself.

Tony