How they behave during an argument
Partners in happier relationships show different body language during conflicts and heated arguments compared to partners in unhappy relationships. You want to show you’re listening and keeping your partner calm during such heated arguments.
Also, you want to look out for signs of aggression, disapproval, and even inattention that might include bare teeth, tightly crossed arms, flared nostrils, finger jabbing at your chest, a body turned away from you, a crinkled nose, and eyes darting around the room.