I miss Luna. I don't think I would as much if it weren't for the fact that Cosmo is acting strange. She has a routine in the last day or so where she walks around the house, presumably to every room, then ends up in the downstairs room and cries as loud as she can. When I call her, she comes and lies down next to me or stares at me. She definitely knows.
And that makes it harder for me too, because I can't stop reliving those last fifteen minutes I had with her. I know it was the right thing, but I'm having such a hard time processing it. I try to engage myself in other things, but I end up just sitting idle, and that's bad.
I know it'll get better, I'm just not fond of the in-the-mean-time. I'm living so much in my head right now, and it's no fun at all. Too much going on up there!
It can take a long time. My cat died in my arms with conjunctive heart failure. Three years later and I can still hear his groaning as he died. I had a really hard time trying to get that image out of my head, and even now, it is hard for me to think about.
For several weeks, maybe even months, I kept "seeing" him around the house. He would walk past a doorway, I could "feel" him jump on the bed, etc.
My other cat went into a deep depression and lost a lot of fur. It was especially hard on him because he never knew life without the other cat around.
Even when you know you did the right thing, there is still a natural grieving process that can't be ignored, as much as we'd like to.
Even now, 7 years later, I still recall in great detail Sassy dying in my arms. For months afterwards, whenever I saw the neighbor's cat (who was also a brown tabby as Sassy was) I'd tear up. Hell, reading about you using Luna made me cry.
You are right. It sucks in the meantime, but it will get better.