Does date of separation matter in NJ as legal separation is not recognized.

My wife and I have been living separately since she moved out. She wants to move in now and might file a divorce eventually. I can’t deny her since it is our marital home.

I want to keep the status quo on date of separation as it will be advantageous to me when it comes to asset division and alimony( I am assuming separation date is used in calculating marriage length)

Should I move out when she moves in? Or just live in separate rooms?