You're right. This is your character she's defaming. Take no prisoners. You might threaten her (and I'm assuming her long suffering spouse) with legal action for slandering your good name. Sometimes just the threat of action will back a nutjob down, but be prepared to follow through if she keeps up her BS.
Hang in there... You got a whole board full of women (and a SEAL who's really good at tactics) at your back.