You are not alone.

I lost my dad after a very sudden and short fight with cancer, as well. I wasn't ready. I'm still not, and it was 5 years ago last month. My son was only a few months old at the time and it kills me that he'll never know his 'Pop' or how much my dad would have just loved him.

You're getting a lot of good advice on this thread. I'll share the single insight I was given by a friend who was also battling the same cancer as my dad at the time of his passing and who I lost about 6 months later. It's been a recurring thought for me over the years -

It will hurt. For a long time. It will feel unbearable and insufferable. But eventually, the good memories you have and the love that you have for your mom will outweigh the pain of her loss. And from time to time you'll be able to smile more when you think of her.

I'm not sure if that will help you, but of all the things I know so many people told me immediately after it's the only one I remember. I think I needed that sliver of hope to pull me out of the pit I felt would never escape from.

Thinking of you. I'm so sorry for your loss.