Just look for a better job. This is obviously eating you up for no gain. Life is short and full of opportunity. Me and the Shelties hate change as much as anyone but sometimes it is the thing to do. Instead of stressing on these people figure out where you want to be in 5-10 years and start going there. You are obviously talented and capable given the prior successes here and the med stuff. So figure out what you want to do get training if needed and @#$@# these guys (well wish the well but also well away from you). Good luck
Less than 4% unemployment rate. Lowest in 50 years. Go find a better paying job. You're boss may be right, you complain too much and take little action.
Who knows maybe the boss showed finally and now he is in jail for decapitating him and riding around the warehouse with the head on the end of a forklift fork. Well or has a new better job and is busy because he absorbed old sheep wisdom.