Hard time thinking of my mom

I lost my mom on October 10th, 2011. I live out of town but was there for the last four days of her life. I experienced so many wonderful last moments with her. We laughed mostly and I cried telling her it was ok to go. She had cancer. I was glad I was by her side. I thought, soon after her death, that it was a great way to help me cope. I felt like I would be ok. But here I am January 2012 and I try soooooo hard to think of her and those last few days but when I try, I can physically feel my brain not letting me. I am wondering if anyone else has experienced this. I feel like it is all blocked out. Wondering if maybe this is part of the grieving process. I can't seem to find anything online that says anything close to what I am feeling. I want to think of her. I can look at her picture but still have trouble "thinking". Thank you for the opportunity to write on this page.