In the words of the famous rabbit hunter Elmer Fudd, "Therws Sumthin' Squooey Goin' On Awound Herw"
She is keeping you in the dark on purpose. It sounds awful and is unfair of her to send such ridiculous mixed messages. Holding hands with you for appearance sake and moving out? What the Heck???
I guess I would talk to an attorney. I know that sounds drastic, is drastic, but it is what I would do. She wants carte blanche to come & go in your life and have a secret life too.

I'm sorry. This sounds incredible and sad and she seems very insensitive to not realize how hurtful this is.
I can only wish you the very best as you move forward...