For all those that have a friend with mental issues

Damn this is something so hard to deal with and it's making me so sad hearing people struggling and how they ruining themselves even more because even if you tell them what it is and how to deal with it they won't understand what so ever, it's such a bad emotional illness and I want to help and feel so bad because i can't do anything especially online were you can just hope they stay on and answer, that makes me sick seen such a kind funny person going down into pieces it breaks my soul. Just *sigh*