Codependency and Grief

My father passed away a month ago. He had leukemia and was in hospice, so I thought I was prepared to deal with the grief. When he passed away, I was overcome with anger. Anger towards lots of people. One of the things that came up was a grieving for my childhood. When I was younger, my brother, who is two years older than me, had severe learning problems in school. I tutored him, I saw him get bullied and struggle and all along my parents told me I had to take care of my brother. My father would always tell me, "when I die you have to take care of your brother." So I was the perfect daughter...never causing trouble, and when my brother needed help as an adult, I took him into my home...ignoring my own life.
I thought I had made peace with that years ago, but I guess I never grieved for the loss of my autonomy. After my father passed, I had a lot of anger toward lots of people and things and one of my best friends who didn't call or come to the wake. I think we both do the co-dependecy dance.. and that's why we found this familiarity and common ground. When things are good in our friendship, they are great. We re-enact the relationships we had with our parents through this friendship. After my father died I became upset at my friend, "Peter" for being distant and not comforting me. He blew up at me and doesn't want to see me. I am a people pleaser and am trying to mend fences...I can't stand disagreements, I want to make everything ok....but I can't.
This is killing me because I feel guilty for having all this anger. I've read codependency and grief books. I realize that overwhelming anger is a part of grief, but I still feel guilty and ashamed that I cannot make everything ok. Any advice or wisdom? I keep obsessing about this issue and it's bothering me because I'm normally a logical and sane person.