This must be different for everyone. I assume you went to a different school/program for your various degrees? I don't think the difference is masters vs. doctorate, or even one field vs. another.
Regarding the "mind rape," I'm getting that now in my clinical work and it's making me bat sh** crazy. Sometimes I think I'm on the edge of a psychotic break, seriously. But I have a completely manipulative, needy, socially inept loony bin for a supervisor. My point is, I keep telling myself that it's not the work, it's the people involved that make it or break it.
Edit: I just want to add that I think the constant changes are part of the process for anyone. The "I think you should change X to Y," resulting in the student changing X to Y, followed by, "No! Don't do Y, it needs to be X," even multiple times, seems very common.