We get asked some form of this question regularly. Sometimes people even call the Sass phone to ask if we want to adopt a dog they have that they can no longer keep. It's always difficult for us to thank them for thinking of trusting us to take good care of their pet, but we have to tell them no.
For us, it's not the right time. I have no doubt that there will be a moment when we are ready to bring home another dog (and it will be from a rescue or a shelter), because I've never imagined our home without one.
It's pretty simple, really. Even though Sassafras isn't with us, we still feel like we have a dog, and she needs a lot of our attention and our help right now.