Until a year ago this was someone that walked in the door and left her cell phone on the counter top and would maybe check it for missed calls 2 times in an evening. Her parents and friends always called me if they needed to talk with her because she never bothered to carry her phone around. Now she's a social media junky and I assume obviously flirting on it as well since she's attached to it even while playing with the kids and cooking. You wanna talk complete 180's!? I just don't know this person.
This is WAW 101. My exw and I used to share a phone. Then she wanted her own and was constantly on it doing god knows what. This is all part of the script that will eventually run it's course.
Just so you know I lived with my exw for 14 months after she filed for divorce with zero house rules other then making sure someone was watching the kids. I survived so you can suck it up for a month and a half.