I share your frustration. At one time I was in DRIVE but I withdrew when they supported a candidate I knew had willingly helped a company weather a strike with state tax dollars disguised as the Economic Development Commission. That candidate was William Jefferson Clinton.
I never one time considered withdrawing from the Teamsters though. The company in general has been better than it has to be & that has help attract & retain good employees. That being said, the only reason a company loves you is if daddy owns the company. You should realize nobody at headquarters loves you regardless if you are Teamster or not. You are fortunate to have a contract that for the most part is followed by the company, not because the company loves you but because there are consequences for the company if they do not abide by the agreement.
When you make a mistake, & you eventually will regardless of how devoted you are, you are not at the mercy of some lower level management type tyrant because you are working under a collective bargaining agreement.
You have a pension & benefits that few in the trucking industry have. Handshakes & verbal agreements are not enforceable when those who made them develop amnesia. You have a contract that is enforceable.
I have been a Teamster much longer than you. You will be better off to cool off & think this through before you make such a huge decision that will affect you for the rest of your life.