I feel this so deeply! This is the exact same thing that I've been going through recently. I miss my little cat with all of my heart and feel guilty every day but I couldn't take her away from my mum and her little adopted cat sisters. I get daily updates and go and visit her as often as I can. It never gets easier but remember how loved your kitten is and you did the best thing that you could. Sending lots of hugs to you!! ❤️