Welcome Leslie to a club none of us wants to be in. I am so sorry for your loss. Even if death is expected it still hits you like a steam train when it happens. You will be numb for some time and experience thoughts and emotions you did not think possible. As you are finding they come out of the blue. There is no remedy, take whatever help you can get. Even if you don't feel like eating, which you won't try to have small meals and to get some rest even if sleep is elusive for you. Friends and family mean well, sometimes they can be a clumsy with words, no let them bother you, its hard for people to help and support and mainly they try to find something comforting to say but because we are sensitive it all seems to come out wrong.
Do you have family or friends around you? This can be a good thing but can sometimes be overwhelming so just do what you think fit for that moment in time.
Take care, you are not alone, I cannot give you peace of mind or your hearts desire but I can wish for tranquility and hope for you.
It is unfortunately fairly normal to have the feelings of not wanting to be here. Please if it gets to bad consider getting help as there is plenty out there.
Wishing you a better tomorrow
Pam