Silence becomes strategy when speaking would only teach someone how to deceive you better.

Every response tells the other person something about how you think, what moves you, and where you are vulnerable, and that is fine with most people. With someone who is not acting in good faith, it is material. Explaining yourself in that situation does not persuade them; it improves their next attempt. Silence there is not weakness or sulking, it is a decision to stop supplying information.

When you feel the urge to justify yourself to someone you do not trust, notice what they would learn from the answer. Say less, and say it plainly. Save the full account for people who have earned it.