My friend’s experience mirrors mine. Writing a dissertation takes a certain amount of discipline. That said, I didn’t expect my own committee to try and sabotage me. One of my professors sent back chapters with extensive negative feedback. So I blocked out entire weekends to revise and edit.
I had this happen out of the blue with one of my committee members too. Everything was fine for over a year, until suddenly it wasn’t.
I ended up busting my butt to rewrite about 60% of my dissertation. But, at least he finally accepted the revisions and signed off.