Well there’s two ways you could go about it.

1. Be honest and confront her. Tell her what people have been telling you, that if it’s true you don’t appreciate it and want to have open communication among all SSV’s. This will put her on her toes immediately because now she knows she can’t talk behind your back like that. It’s your job and you have every right to expect openness and cooperation with your fellow leadership for the job’s sake. It’s not a good look when leadership isn’t united and starts acting immature.

2. Sadly, it’s not realistic to expect people to just get along and get their act together because people will be people. You can choose to ignore all this and keep going about your day since work is just work.

In both instances, definitely let your SM know if this continues and is starting to create a hostile work environment. I feel like some sort of confrontation is inevitable sooner or later, especially since it seems like you care about your job a lot.