Am I losing my mind?

So I think there may be someone repeatedly sneaking into my house and cleaning it and losing things. Last night when Ben got home he said "Thanks for cleaning the house." I said that I hadn't cleaned, I thought he meant, thanks for not making a mess, but he didn't want it to sound rude. Anyway, this morning he couldn't find his keys, he had left them on the desk, which is where he always leaves them, and they weren't there. Then he mentioned that I had cleaned off the desk yesterday. It did look cleaner, but I DO NOT remember cleaning it, I just assumed he had. And now, his keys are nowhere to be found! I saw a woman on Dr. Phil that had new twins, and was so absent minded that she forgot to pay bills so much that their electricity had been turned off twice, and their car had been repossessed. It wasn't that they didn't have the money to pay the bills, she just kept forgetting to put the check in the mail.
Could this be happening to me? Or do we have a creepy good Samaritan? This isn't the first time he's accused me of cleaning when I could swear I didn't do it! I'm kinda hoping we have a creepy good Samaritan.