After I cooled off (I don't do well with people mistreating my friends), I agree with everyone else. I think a new environment will do you good. Your new job's gain is the old shelter's loss. It is amazing how trivial people get...you should see some of the teachers at our school...amazing that we are supposed to be professionals and end up acting like the kids sometimes. Just show them that you've above all the trash talking and back stabbing and walk out on your last day with your head held high.