Sorry to hear that. Lots of people can't relate to cats much, but my cat Merlin was my best buddy after my wife passed. He was about 12 years old when I had to go in for heart surgery, and no one would take him in while I was in hospital. So after exhausting all my options, I was in the position that I had to have him put down. It broke my heart to do that, so I know how you feel. But 22 years is a good long life for a cat. My prayers are with you.