My Sweetie looked just like your friend's cat. I took him into the vet after waiting 10 days (closest appt they could give me) only to find out he was in a diabetic crisis. I have no idea how old he was... and he'd never presented as diabetic. He'd passed a physical just 2 months prior with flying colors. I took him in on a Thursday. I spent most of Thurs and Fri with him, but of course couldn't see him on the weekend. I was headed in to see him Monday morning when I got the call that he had died Sunday night.
I beat myself up for not yelling or demanding an earlier appt for him than they'd given me. But the vet was good and rarely left him alone. She'd just lost her dog the week before. She was hurting and knew what I was going through. And then all I could get my head wrapped around was I wasn't there with him when he died. And I still get wrapped up in tears. Next Ides of March will make it 3 years to the day I lost him... and believe me, it hurts every bit as bad today as it did then. I will always feel like I failed him somehow, all the while he'd stare up at my eyes with the most trusting look. There are sometimes, like right now, where it feels hard to breathe it hurts so bad.
So my deepest sympathies to your friend. I hope she can find out what happened and why... it might help her come to terms with what's happened. Meantime, all you can do is be close for her. Bless you.
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