Good morning Mrs Jones.
Things situations are so frustrating. Exactly, "The Gambler." Getting into it with a person with this behavior is quite tricky. If they don't act old enough to behave better, difficult to win any battles. If you do decide to confront her, be careful, do something creative so she will get the message. Like tell there is an issue to discuss and have the boys there, or everybody's husbands, so the behavior is identified and addressed in the "scriptural" way and with witnesses. (barf) That usually stops it cold.
I had a relative that was gossiping and slandering. He is a servant, but I counciled him with scriptures about lies and slander. I told him if I ever heard anything again coming from him, I would talk to his elders, and if I didn't get satisfaction, I'd write the society until I did.
Your judgement is wise. Vent here all you want. Say "hi" to the rest of the fam.