One of the most truthful things said here in SI is to take what you need and leave the rest. If reading in a particular forum triggers you, take a break from it. If you need to walk away for a while, do so. Do what YOU need to do, for yourself. It doesn't make you a bad person or an uncaring person. It just makes you human.
BTW, I completely empathize. I still open certain threads and realize that there is nothing I can contribute because it somehow hits too close to home or triggers something in me. I just close them, try to say a little prayer for the person posting, and trust that one of our on-line friends will have their back. (((hugs)))