Big Hugs Sister!!! We all have it at some point in our lives. I missed out on my daughter being a baby due to divorce.
Not that this makes it easier for you - but Cesar Milan says - Dogs live in the moment - they don't remember what you did or didn't do 20 minutes ago. She's just glad you made her pup cakes and had a birthday party with her right now.
Life is a string of lessons...I am not afraid of tomorrow, for I have seen yesterday and I love today!