Loss and grief

I lost my best friend 6 months ago to colon cancer. I somehow thought that it would get a little easier to deal with losing her as time went on but it hasn't happened yet. I miss her every single day. My daily thoughts are consumed with the memory of her. I am angry at everything. I never had a lot of friends growing up, I never felt the need to. She and I met the first day of kindergarten and was inseparable for the next 33 years. I have aquantinces that I talk to from time to time but no one I consider my real friend. So I guess I've been holding a lot in as far as dealing with her death which was horrible to watch because we knew it was coming. She went through pure hell and there was nothing we could do. She was diagnosed in October of 2013 and had 11 rounds of chemo, numerous hospital stays, wasted away from 220 lbs to 67 before she died and we were helpless to help her. She left behind 2 amazing children ages 15 and 13 and my heart breaks for them every day. She was an awesome mother. She was a part of my life for as long as I can remember and I'm finding it difficult to enjoy life without her. I don't understand why this happened to her; I'll never understand it. Every fiber of my soul grieves for her.