A question mark is a hook; a period is a door closing. Pick your punctuation on purpose in arguments.

Punctuation sets the direction of a conversation. A question keeps it open and invites something back, while a full stop closes a door and dares the other person to open it again, and in an argument you choose between those constantly. Most fights get worse at the exact moment somebody switches from asking to declaring. The content of what you said matters less than whether you left a way through.

In your next disagreement, replace one of your statements with a genuine question. Not a trap. Something you would actually like the answer to.