I just came across this thread. First let me say how very sorry I am for your loss. I lost my eldest female Border Collie about 2.5 years ago (she was almost 11... cancer). We did surgery and it was looking good but she took a turn and I had to let her go. And then my other female Border Collie a little over a year ago (she was almost 9.... heart condition). Knew something was a little off so took her to the Vet. She had a full blockage and would only have survived a few more days so decided to let her go. Both, of course, were very unexpected. I still have my male BC (who just turned 10 years old last week) and my new'ish' spaniel mix female I adopted after my oldest BC passed. She is 3 1/2. I really feel for you and I'm sending hugs your way. Here is a poem I came across after losing my most recent sweet girl.
I lost a treasured friend today
The little dog who used to lay
Her gentle head upon my knee
And share her silent thoughts with me...
She'll come no longer to my call
Retrieve no more her favorite ball
A voice far greater than my own
Has called her to His golden throne.
Although my eyes are filled with tears
I thank Him for the happy years
He let her spend down here with me
And for her love and loyalty
When it is time for me to go
And join her there, this much I know...
I shall not fear the transient dark
For she will greet me with her bark.