We went through this last September with Mimi at 15. It's really hard to make the decision to let them go when there isn't really anything wrong with them. Mimi was really alert, still eating, etc. But she was having trouble walking, peeing & pooping in the house all the time and kept getting herself stuck places when we were at work, no matter how we tried to contain her. It was hard right up until the end, and I think if either of us had waivered the other would have caved and put it off. But, as hard as it was I still find I'm at peace with our decision. I didn't want to come home and find she'd broken a leg being stuck somewhere. PM or email me if you want to talk about it.