Legal Question in Family Law in Connecticut

"Acting like he does not know where she is...". By that, I assume he's perhaps filed for divorce and asked the court to allow him to notify her of the divorce by publishing notice in the newspaper because he doesn't know her address where to serve her with papers. As to that situation, she can remedy it by filing an appearance, either as a self-represented person or through an attorney. I don't know if there are children involved or if they've been married long enough so that she'd be entitled to alimony, or if there's any property involved, but if she does nothing, then anything she might be entitled to may be lost.

As to the identity theft, how do you know this? If you have proof of some specific instance of the girlfriend impersonating your friend, notify the person who has been given the wrong information and correct the situation. If she's using the friend's credit, for instance, she should notify the police, but ID theft is pretty far down the list of police authorities.