Is this true?

When my mother died, I felt really unhappy - not because she was dead, I was glad about that as she was having a very disagreeable time before she died.  And she wasn't suffering in silence either.  What made me unhappy was the very negative feelings I had about her death.  Every recollection would be of something unpleasant she had done or said to me.   I couldn't find anything positive, I found things she had said about me to other people especially hurtful (idiotic of them to tell me - but old people have funny ideas about which of their reminiscences will be appropriate - or perhaps they think any reminiscence is better than none.)

For a long time I struggled with these thoughts.  I found a friend had had a similar experience, which made it bearable - I had mourned her from the time she became ill - but once she died I didn't feel good about it at all.   However what occurred to me is that, perhaps that response to someone's death is actually a sort of defence mechanism, that this anger and dislike prevents one from being overwhelmed by other, more depressive feelings, feelings that might make one unable to carry on, to go into a decline, temporarily at least.  Anger as a method of psychic self-protection?  An idea to try out on Simon I think.  Or is it an evolutionary biology query that I could put to someone else?