My 14 year old indoor/outdoor cat has been diagnosed with diabetes. I travel for my work, so am unable to provide the twice daily insulin injections. But I did change her diet to all protein. Over the past 3 years she has gotten thinner, slower, and weaker, but still visits for caresses. 

Trouble is, she is urinating all over the house. I try to keep the litter box clean, but my husband is ready to feed her to the coyotes. Even my love for her is laced with resentment at this point. 

At what point will she be truly suffering with this disease? How long will she live? I have never put down an animal before and prefer not to, but certainly don't want her to suffer.