If the locket was a horcrux then it's no wonder it made you think all sorts of untrue things.

Like the diary did with Hydra.

Mr Dumbledore was here to talk to Mr Snape and Sirius about the horcruxes. To try to figure out how to find them and destroy them, I think, but I wasn't really paying attention to anything else going on then, so I don't know what they decided.

I guess everyone is broken, one way or another.