How do you deal with an 'on the way out' pet?

I couldn't man up enough to shoot my cat anyway.

That's what friends are for.

Don't put it off till the animal is suffering in the middle of the night. My mother had that happen with her dog. Went into suffering. Only option was to have a family member take it out and do it.
Or wait.

There is something else you could do. But I would get flamed. Not that it's inhumane.
Just not a popular thing.