Since or if you placed your elderly loved one in ALS or a nursing home. did you have to contend with opposition from meddling relatives such as a niece, cousin. etc. I just had to confront my mothers niece who opposes me putting my mother in ASL. She lives in another town so I confronted by phone. I told her off in uncertain terms and let her know that she the niece and the daughter and she could not override by putting ideas into my mothers head. I threaten to bar her from visiting as well as intercepting her letters. This so called "niece" has never done much for my mother and now she wants to put on the judgemental act.
-While your cousins may not have done much for your mom, they still may genuinely love her. It may be hard for them to see her aged related decline. My mom is like an icon with my cousins - they're having a hard time accepting that their rock is now this frail lady. They're going to believe what they choose to believe, no matter what you say so you need to come up with a couple sentences to say, calmly. Acknowledge her love for your mom then a brief statement about your mom's need for more care.
-a few relatives of mine are drama queens, which may make me nuts, but my mom loves them and the drama. Sure their calls may get her "wilded up" but she loves it. It's a pain to deal with the fallout but I'm not getting between Ma and the kinfolk. I'd recommend you consider doing the same .... picking your battles.
-when you're doing everything you can to help care for your mom, that is the thing that helps you ignore what's being said by others in the wings. Throw it off.
There are folks who like to stir the pot. Don't give her any notice or feed her negative energy. If you need to, say sweetly, i rather like having my mom tended by professionals who know what they're doing, not a rank amateur like me.