So what you do is go on about your business like you didn't even notice. She's on the phone, go out with friends, leave a note saying, hey wanted to go out but saw you on the phone. I'm out at XXXXX with my friends give me a call if you wanna join. If she starts giving you a hard time, tell her to get the fuck off the phone and she can join you in life.
I think you should at least have a sit down with her and talk to her about your problem. She might not think what she's doing is a problem, and unless you tell her, you're not giving her the chance to fix it. If you tell your problem and she still does it, then I would take consideration of leaving her.