Suz, I have felt I tried to be 'too good' of a mom due to my first child being stillborn. I felt I had already let one child down by not being able to keep him alive to birth. I had to be an extra great mom to my new baby so she would not die, too. I know - but it is what I thought then. My difference from you is I was too patient and too kind. Probably got walked on a bit by being too nice and friendly with difficult child.
I am glad Rob was able to tell you his honest feelings about your relationship. That will go along way to your future relationship.
Glad your brother is there for support!
HUGS!
