I read PM and LOVED it. It helped me most in understanding differentiation and how emotional fusion has played a role in all of my relationships, not just my marriage.
I felt like there was a bit of my situation in every single case. I underlined points that hit home.
The part about sorry vs. remorse... After I read that, I cried and cried because it hurt so much to think that my H wasn't compelled toward remorse all these years. Sorry just doesn't cut it. I'm over it, though, because I realize that he wasn't able to get to remorse because he couldn't possibly understand my end of it.
It is not an easy read, but it is well worth it. I plan to pick it up again and again. My H saw how eye-opening it was for me, and now he plans to read it.