No apologies needed. Please take care of yourself (as well as your cats), it’s very hard to put a time limit on grief.
Like others, this is painfully familiar unfortunately (especially the shock from them deteriorating rapidly after being fine mere days ago). The scars never really fade, but you’ll find a way to cope with time. But until then, we’ll all be waiting patiently 🙏
Take heart that Garrus lived a life feeling warm, safe & loved. I’m sure one day he’ll be with you all again.