Due Date Changes

My dr is driving me freaking nuts! He has changed my due date SIX TIMES in the past two and a half months. He has never given me an estimated weight or length for the baby. He never measures anything but her head. He's been adding and subtracting weeks my entire pregnancy. He refuses to take my past pregnancy and baby size into consideration, even though he was my dr for those too. I've lost 13lbs this trimester and haven't gained any back and I only gained that amount to begin with. He just tells me that "babies are like parasites, they suck mom dry." I know for a fact that he's at least two weeks off on the due date. On top of everything else, I've been engaged for weeks, he ignores most of what I say to him, ignores that I tell him I'm thinning and effacing and I'm 1cm dilated and refuses to give me a pelvic.And I'm pretty sure I'm too far along to find another doctor.