private
You should maybe put some time aside, here and there, to think about her. Just when you feel up to it. Gradually, it won't hurt as much, until you can think about her and smile before your heart gets a twang.
It was... odd. I have been able to hold fast to many good memories of my mother, I am lucky in that I did not lose her to an illness. I am sure it was harder for you to see, and I was so much older than you. It is difficult, but I feel able cherish her a little easier maybe.
I am mostly shocked by those who are horrible to their parents but then suddenly believe a single day is a day to be nice or talk well of them.