"helping people and listening to their problems has positive benefits in humans mental health" is this claim true or there are exceptions?

Hi everyone! How everything going?

So, I'm (autism, schizoid) asking this question because a friend of mine (ADHD, depression) is currently going to my previous psychologist and he shared this advice with my friend now.

He's going to therapy over his possible dysthymia, but he was always extremely sociopathic and cruel with others if they showed weakness or sensibility, almost 3 of his partners broke up because of this.

Fortunately, my friend was never cruel to me but now he's trying to be more kind in his personal relationships, and based on what he told me: he absolutely hates it.

According to him "almost everyone has corny and stupid issues, young people nowadays kill themselves over shit like cyber bullying, grooming and blah blah blah... What's the point of helping others if you have worse problems?"

That last line stuck with me, I don't mind being nice and listening to others but I don't do this because it brings me happiness, it's more like a "reflex" that escapes my body.

What do you think? Is being nice and kind not for everyone?