Think about the values your grandmother had and let them live on through you. Perhaps creating a nice photo collage would be something pleasant for you to look at now and then or hand down to other family members. There are many ways you can keep her memory alive.
I understand how you feel, it's been 6 years since my father passed away and it really does feel like it happened just yesterday. Not a day goes by without me thinking of him in some way, some days I have many more thoughts than others. I think of him as a good dad who did all within his power to make sure me and my siblings were safe and had the things we needed.
I also try to think about how he would do certain things and in the process I have been able to help a few people out. Talking about the good times is always my favorite because it makes me and others laugh, even if they don't know my dad.