Well Tamirra he's your baby, so naturally you will miss him, especially if you found him to be a lovely son. You've been a mother for a good part of your life and it's become who you are, to an extent.
I don't know your situation, but to take your mind off things, keep busy, perhaps take up a few evening or dance classes, meet other people, start doing things you enjoy and put yourself first.
The one consolation is, you will soon have Granchild, who you will be able to bond with.