Chances are they know they are using you as an emotional tampon. Most people won't entertain their bs, and they will use you as an emotional dumping ground

I would just tell them to seek counseling as you have better things to do and don't want to be dragged down by their negativity.

This is how my dad was with me. I used to try and listen and give advice, but he never did take the advice and only ruined my mindset. My other siblings are more nefarious than me and would use that information against, criticize him or even turn the tables and start unloading on him. The only thing that put a stop to that was having firm boundaries and cutting him out of my life for not respecting those boundaries.