I'm am so sorry for the loss of your sister. I can't imagine the pain you must be feeling. I will say a prayer for you, your sister's son, his father and the rest of your family. I've known a few people who have committed suicide, but not an immediate relative. For me, each time I felt such a sense of sadness for the loved ones of the deceased. I hope you will find peace sooner than later with regards to this. I know it must be so painful and difficult.