Positives?
I am helping someone who now laughs when I say "consider the benefits", it is our catchphrase.
I couldn't be more serious and she knows it but it is a slow process and who knows what real effect I am having.
In this case she is not what we would call suicidal (as far as we can tell) but is definitely that low.
The problem is that people being positive and suggesting things is the last thing they want. AND The first thing they need
and there we have the nub - the gap between need and want is too great - result unhappiness.

I did see a report in New Scientist that the effects of losing weight quickly has many of the same symptoms as depression. In retrospect it rung bells with my youth and more recently with someone close.
the comfort eating that preceeded it in the latter case was a clue to unhappiness we all missed.
Does this apply?