That's a good investment in your best friend, I'm glad she had so many years of love with you! Quality of life is crucial, to me. I won't prolong their suffering for my own sake, especially given we can't explain to them what the tests and surgeries are. I've been fortunate that when serious things have happened, it was a pretty clear solution after initial tests. Mostly they were young enough to warrant trying (and they recovered). My 15 year old in renal failure... It hurt when the tests showed her decline, but we were able to let her go with love, before she suffered any more. Mine have needed special diet and medications for various things over time, but imo if one isn't willing to spend/sacrifice for those they've committed to, they don't deserve them and shouldn't be allowed to have them. When people tell me 'it's cheaper to get a new pet', I judge the hell out of them. Really shows you their character and the value they place on 'loved ones'. (I feel that way about parents and human children, too. Too many lazy, shitty parents raising kids that didn't ask to be born into that.)