Ten Years..still grieving

My younger brother drowned in front of me at his birthday party on August 25th 2001, He was turning thirty..he drowned on his B-day. he was a best friend to me. I talked to him almost everyday, could talk to him about anything...he listened , didn't judge. I was comfortable with him.  He helped me get through math classes in college. He was my play mate as a child.  He lived with me in our childhood home, when he passed away. The part of all this I know I need to heal from is the part that naggs me still....could I have saved him? He was floating and my other brother and I thought he was joking as he did so often...the ten year annivarsy is comming up...things are so differant now...  I will be mourning by myself this year, August 25 is thursday.