More inappropriate pooping

I've been dealing with this all summer, and I'm to the breaking point-

Alcott is toilet trained (no litterbox). He has never had a problem with this until BOOM, one day, he starts peeing and pooping on the couch downstairs. It's escaladed from there-- pottying on my bed, laundry, blankets left on the floor, etc. I've taken him to the vet-- he had a bacteria infection which was taken care of (and has been for several weeks now).
If I lock Alcott in the bathroom, he RARELY has problem going in the toilet. But give him free run of the house, and he RARELY will return to potty correctly!

Many people tell me to give him a litterbox instead of the toilet-- this is frustrating merely because I think his willingness to use the toilet correctly when in the vicinity shows that the issue isn't with the toilet itself.

I HATE to lock him in a small bathroom all day, but I also can't ruin my furniture and linens by having them covered in cat feces and urine. Nothing has changed in my daily routine that would lead to him being stressed, and there have been no new additions or changes around the house. It really was totally out of no where! I've also been rewarding him when he uses the toilet correctly.

Please help! I love my cat but I can't live like this! Any thoughts? I've read the other inappropriate pooping threads, but I've tried all those suggestions...

I've supported your efforts in the past to train your cats to use the toilet, as I think it's a great idea if they'll actually do it consistantly. But it does go against what their instincts tell them to do. I think you probably need to throw in the towel and just get a litter box. Alcott must prefer a more "natural" way to go potty.

Yes, I'm thinking he is looking for a more natural medium in which to go. Hey, and anything is better than what you have now. Even if it was only occasionally, it would be hard to tolerate, but all the time? Yikes, no wonder you're at your wits end.

I actually did give him back the litterbox for a little bit-- and when there was no improvement I went back to the toilet. In fact, while I had the litterbox out, he never used it except to dig for a bit...