https://medium.com/p/d96f431f4e8e
Money quote:
Around the end of 2012, Julie started dating a close male friend of the cofounder’s wife and didn’t like that they were close. She asked them to stop being friends and when they would not end their relationship, Julie started telling coworkers that the wife had affairs and that the cofounder’s newborn child was not his. She told this to multiple coworkers directly and also to the wife through her boyfriend.
This is where the wife reached out to her and the rest of her story starts. All of Julie’s story involving the cofounder’s wife occurs only after Julie was spreading vicious rumors about him to even new employees.