That conversation with your mother sounds so painful. It's hard when people in our lives say things like that about a beloved pet, even when it's well-meant in some way. Many people don't really understand what goes into managing a chronic condition in a fellow human, much less a cat. You and Indy are taking good care of one another, even though it's really hard sometimes.
And as a fellow parent of a second-round FD cat, it really does seem to be a lot harder after remission. Sympathy and solidarity if you want them! (Also much as I value it, I do think the Libre, the constant data, can add to the stress! Which may be part of why things feel as different as they do to me this time, though I don't know if it's the same for you of course.)