You can do everything you're supposed to do and still not have things turn out okay. That's just how it happens, I guess.
Don't criticize people's coping mechanisms, especially if you don't know all that they're going through. Maybe their coping mechanism is why they're talking to you in the first place. Maybe they're only talking to you because they wanted to let you know that they're struggling.
When you've got chronic illness, you're already dealing with shit everyday. Sometimes when life throws stuff at you it's on top of everything else you have to deal with, and not everyone understands that.