I'm so very sorry. My first greyhound, Frostman, died in his sleep without any warning. That was 8 years ago. Having lost dogs to illness and without warning, I have to say -- for me -- the shock of the unexpected was harder for me to deal with. People will sometimes ask me why I continue to put myself through the pain. For me this poem says it all.
Fragile Circle
"We who choose to surround ourselves with lives even more temporary than our own, live within a fragile circle, easily and often breached. Unable to accept its awful gaps, we still would live no other way. We cherish memory as the only certain immortality, never fully understanding the necessary plan." -- Irving Townsend.
We all grieve and heal in our own way and on our own schedule. Only you will know what's right for you.
Again, I'm so sorry.