Maybe just ignore the old name altogether, hon. As if they're literally talking to, or about, someone else. I mean, if folks know your actual name, and choose not to use it, then surely you can't be held accountable for not answering to a name that legally, mentally and emotionally doesn't belong to you.
If no one gets any response to it whatsoever, even if they're being deliberately awkward because they know it will get a reaction, then eventually they'll have little choice but to stop using it since it will have no effect and whatever they want will go unanswered.
I think sometimes, folks do things precisely because they know it will bother someone. But if you don't rise to it, they literally have nowhere to go.
