It might help to understand where you boss is coming from. Maybe he has some crazy deadlines on his shoulders? (do you know exactly why your previous boss quit? speaking of, where does he work, and would he want to hire you there?) Sometimes personality types can clash, too. For example, in the Myers Briggs analysis of personality types, "Sensing" people tend to be extremely detail-oriented, while "iNtuitive" people tend to prefer the big picture. A hard-core sensor will often think an intuitive is being lazy and indirect, while an intuitive may think a sensor is being obnoxiously particular and lacking in a clear objective. Just as an example.
Of course, your boss could simply be a tool.
Try not to burn any bridges, but feel free to see what's out there. Also, crank that stache. Even if you're a long way from FI, building that stache fast might allow you to buy time to figure out your next steps. At the very least, if you can survive half a year without a paycheck, you can sleep a little easier at night knowing that if this guy completely loses it and fires you, you'll have plenty of time to find another job.
Sounds like a sucky situation. I hope things just simply improve for you - that's the best situation =/
(for some reason I got the impression your bosses was a guy, but you never actually stated that. I'm too lazy to edit everything I wrote with he/she, but you get the idea)