When my mother died in 2000, she had been treated with a complete lack of respect and kindness by my Dad (ex), brother, and SIL, both before and after her death. I am sorry I wasn't older and wiser then, I could have helped her more.
I wrote to my Dad explaining why I was so upset, and why I didn't want to have any contact. I told my brother on the phone, having had to go to a solicitor as he was being very secretive about her possessions and the will. About ten years later I wrote to both my Dad and brother and said I forgave them, but didn't want to see them. Unfortunately my SIL seems to be the driving force, my Dad now lives next door to them, and she is now his 'carer'. I hope he checks his cash regularly. None of them know what love or loyalty are, they have very different values to me and I don't regret it, sad as it is. I didn't want any of them near my children or have any influence in their lives.