The faster you get defensive, the more likely they touched something true.

Speed is the tell. A remark about something that is plainly not you draws a shrug, because there is nothing to protect. The heat arrives when a comment lands on a thing you already suspected, and the rush to answer is an attempt to move the conversation away from it. That does not make every criticism correct, only that your reaction is pointing somewhere.

Next time you feel yourself speeding up, say nothing for a count of three, then ask one question about what they meant. Decide tomorrow whether they were right. The pause is what gives you back the choice.