OP...SIL is ridiculous!! She would be univited within SECONDS!! I don't deal well with unreasonable In-laws. WALK THE HELL AWAY!! NOBODY NEEDS THAT KIND OF BS!!
--- Megan is a amoral tool, but I believe she should have been confronted privately (with only parents) not publicly. It was ok to notify her company, but it should have been done after the wedding. OP should have called Megan's bluff before the rehearsal dinner, told her there was no need for her to come to the dinner because Zoe was her MOH and since she therefore wasn't going to the wedding she didn't need to attend the dinner. Could have told the dinner guests that was a conflict of interest and Zoe wouldn't be able to attend the dinner and the wedding. If she had delayed notifying Zoe's employers, she would have been "arrested" after the wedding, so it would have been juicy gossip then, not during the dinner, wedding and reception. Now I wonder will the in-laws press charges on Megan or will her embezzlement be swept under the rug?
The OP did what she had to do. She had to expose her in front of all the family. Besides being so toxic, she was doing so many illegal things. And asking her to have her best friend since childhood uninvited to the wedding no, you never do that.. and then she goes around spreading rumors about Zoe. Really bad person. And before that she was trying to force OP into using her vendor or saying what power she should do this how she should do that. It is none of your business and less the bride and groom specifically asked for your help then keep your mouth shut. They know how they want their wedding to be. They do not need anybody interfering, and how they set up their wedding what venue they choose what caterer they choose what food they choose. It’s all up to them. If they want help, they will ask for it. Don’t try to force your choices on them.