Lost my mom to liver cancer. Don't know how to cope.

I recently lost my mom to liver cancer. She fought bravely for 5 years and held us all together till the end. She finally passed away at just 58 years old beginning of June 2011. I have been simply devastated. It was horrible to see her suffer at the ending couple of months and I cannot erase those images from my mind as I held in my arms and she coughed up blood and was in so much pain. I was there when she took her last breath and I still get nightmares about everything. I try to think of the good times but I simply keep seeing the bad end. I have been struggling with these feelings and never tried to search for anything online. I finally searched for something to help me and found this website and read other peoples posts who have gone through the same thing. I thought I would share my feelings as well so maybe if something else goes through the same thing they know they are not alone. I feel robbed of my time with her. Just when my life was taking a turn when I could start doing things for her, rather than her taking care of me, I lost her. I am just 23 and I had so many wishes to fulfill her dreams which will now go unfulfilled. She was my best friend and I loved her the most in the world. I don't know how to deal with it at all yet even though 4 months have passed. I cannot even look at her pictures as it makes me cry myself till my eyes hurt and I can't cry anymore. It has been 4 months and I thought it would get better but it doesn't. If you have some advice regarding how I can cope that would be so good, or simply share your thoughts if you have gone through something similar.
My prayers and sympathies with everyone who is going through what I have gone through.