What would you do about this cat?

Amy10223

Twenty two yr old male cat, a bit senile because he forgets when he last ate and is asking for food all day (and sometimes at night at 3:00 am). Has a thyroid problem, so I avoid giving hi any fish pet food. Lately, he's been going anywhere he wants; on carpet, in the garage (both #1 and #2), and attempts to go in my bathroom so he can go on the floor. His kitty box is clean at all times, and I have two. He knows its in the garage which is not far from anywhere in the house. Today I placed a box inside the house, by the garage because I caught him peeing by a hutch I have there.

I have thought of putting him to sleep, but I feel too guilty.

Updates
3 mo
My cat isn't do well now at all. Most likely, he will be put down today or tomorrow. He is bleeding from his behind, and I'm not sure if he is in pain or anything--but I don't want him suffering, so it's time. It will feel strange not to have him here--he would be 23 in the early summer.
What would you do about this cat?
4 Opinion