Why do I feel bad? I did the right thing right? Need reassurance!?

This girl at my work who is a supervisor(like me) has been talking badly about me to various staff members and now new staff! I 'm very outgoing and nice, she's cold and very serious. We're at work' no fun allowed 'kind of person. This being said everybody has been telling me what's she's been saying. Last night I'm training a new girl and she says Cindy trained me last night and apologized ahead of time for who was training me tonight' EXCUSE ME that would be ME! So I called her Cindy at home suggesting she wouldn't do this to me.( SHE's 31 and I'm 27.I thought high school was over.) She's stars yelling at me and crying and then says works my social life and my livelihood and you just don't care! OK people it's a family restaurant not brain surgery. So I go on to Say the manager and the owner don't have issues so just keep your comments to yourself especially in front of new staff. She cries and says she's quiting and hangs up.WOW! Am I wrong? People will call you on it if u talk