I'm sorry, I was just in an EliteSTF KASE group from hell and I need to rant.
Yeah, I've seen an increase in the number of assholes in the game (present company excluded...).
I would suggest doing something else in the game until you find a good group to run the STFs. You could volunteer to lead some noobs on the lower missions. I see a lot of players that really have no clue what to do. I've been running the Starbase 24 instance as I've been updating weapons and skills and it amazes me that despite having cockeyed setups at times, that I usually walk away with the choice rewards. So there is obviously a lot of opportunities to provide guidance to the newer players.
If gaming is causing you bad stress, you need to re-evaluate the situation. Find a way to make it fun.