FirstMate and Skar have it exactly right, I think. Even now that she is gone, I would never want to go back and "edit" her out of me or my family's lives. She was such a source of love and amusement that even her devilish ways are just fond memories now.
So... on Friday, Cory and my Mom took her on her last car ride to the vet. I couldn't help but grin through the tears a little when I heard that even though she was very weak and ill, she perked up a little and tried to put her paws up on the door and put her head out the window. She always loved that. So Cory supported her so she could stick her snout right into the wind one more time.
When they got there, I had Cory call me on his cell and put me on speakerphone so that I could sorta "be" there. The vet's office had a lovely blue towel set out for her so she wouldn't be cold on the exam table. (I had my bro bring something, but we didn't need it after all.) I'm so glad that Cory and my mom could be right there, giving her little pats and reassurances. Once the IV was in, and we let our vet administer the injection, her head just wavered, then drifted down and she was gone so peacefully. So fast that I couldn't almost believe it when the vet said Nikki's heart had been stopped for 30 seconds already. It just hit me so hard, though, that she still loved me and my family as much as ever.
I had a dream Monday night. My dad and I were in the old house at our dining room table eating breakfast. And she went to the sliding glass door, and put her little paws up there, yapping to get my attention. Clickety, clack, yap, yap--she wanted out. So I got up to open the door and she made a few little leaps of joy as I approached. Suddenly, though, she just faded away. I turned to my dad, who had gotten up, and I just cried into his chest, saying, "Oh, Dad. She's gone from here now, isn't she?" Then I woke and yet felt comforted. It was like she visited me--in her own special way.