, how long have you been divorced? I noticed the last time you posted was back in 2014, and in MC. I'm not going to say that 9 months is too soon to introduce your SO to your kids because that depends on the couple, IMO. My brother-in-law was a friend of my sister's for a few years before she divorced her husband over his infidelity, and he was around regularly. And I don't see anything wrong with having dinner a couple times either... JMO. But, I do understand why some don't agree with my opinion on that matter.
But, I do agree with what Hope said. YOU are the parent... you are not her friend. Your daughter is having a difficult time adjusting because, first, you are being a friend to her. Second, she has gotten confused because of all the living arrangement changes. You slept in separate rooms for years, and then divorced. From the timeline, it seems you were divorced, but still living together? No wonder she's confused!
You have been seeing him, exclusively, pretty much since you moved out of the house. How do you think she sees this? For that matter, your older daughter may see it similarly. No, it does not excuse her behavior, but it does give you a look at what she is thinking.
As for the password and devices... For goodness sake, change your passwords and make sure she can't see them! And don't allow her access to YOUR devices.
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