Call it guilt tripping if you like, but many of the replies are just out of concern for the cat. Last mention of a visit to the vet was in May, and Deb has not said otherwise. In August she said he was crouching by his water bowl and not drinking or crying while drinking. Now it's already November and there's no mention of treatment or medication for this cat.
IMO, if it takes a little guilt to push Deb into action to relieve Gus of his misery through drugs or euthanasia, then that's great. If Gus could know, he'd be thankful too.
Deb will do as she will, that's her right. I will support her decision if it's medical treatment or euthanasia, but in no way, in good conscience, will I support anyone who allows an animal to suffer until death with no intervention. That's my opinion and feelings on the matter, it's very frustrating to hear of an animal suffering for months with no action taken on their behalf. A lot of us here, including myself are animal lovers and we truly care.
You don't have to euthanize Deb, but at least get him to the doctor for some medications that will help him through the daily pain.