I'm so very sorry to hear about your loss.
Grief is an emotional journey and there is no way to know how long it will take to feel better. They key is to work toward acceptance and peace-of-mind because the love you have for your mother & the memories you shared will never fade.
I found during my experiences with the loss of loved ones, writing is very cathartic. You could start a journal or a memory book of your mother. At times, I've written letters to the person I lost and poured out my feelings. These types of activities help you gain closure one step at a time.
Good luck to you. I hope you can begin to heal in the best way possible.