I had to euthanize my beagle many years ago, for similar reasons. To see him go from such an active playful dog to a year later dragging himself around was painful. Yes, I felt so guilty for doing it, and so wanted the vet to take it back right after he gave him the shot. But, it was too late and in a few minutes he was in doggie heaven.
Oh shit, now I'm crying.

I made the appointment for next Thursday. I worried about Shelby, she's never been without Saleen. I know it's probably the right choice. Let her go now, so she won't have to watch her degenerate more. But she is still happy. I don't want to see her not happy.

It's never an easy decision to make, being an ultimate final result. The question really is, are you being selfish by keeping her alive, or being selfish by letting her go?
*Massive bear hug*

what about trying to rehome her?? What about special corgi rescues that will let her live her life with treatment she needs? Just because you cant afford it?? If she's happy and pain free let someone who can take care of her, take care! This breaks my heart, and you're already planning on getting another puppy.,..??

Please try to rehome her. Spend ALL OF your free time off work looking for places that will take her.

Rehoming her is not an option, the stress of it alone will be horrible for her. She can barely stand to be away from me when I go to work and if I take her away from me and Shelby she will go crazy. And with this disease it will klli her within 6 months. it's not like I'm cutting years out of her life but saving her a month or 2 of misery. She can't move. Her back legs are completely useless and her front aren't much better. Her life consists of being carried out to go potty, then being carried back to her bed, that's it. She can no longer control her bladder and often I will come home with her soaked in urine or sitting in poo.

That won't change if I rehome her, all that will mean is that she will spend the last month or so of her life scared and shuffled around from place to place.

There is no treatment for DM, nothing I can do to stop or reverse it. So being able to afford treatment is not a point in my situation. She's gotten to the point that I cannot keep up with her care and I won't watch her deteriorate any farther. I won't do that to her. Once you've seen your happy, healthy dog go from being active and running around to not being able to even get to the water bowl in less than a year, then you will understand my position.