The silent treatment is usually about control, not needing space. By withdrawing all contact and warmth, the person makes their disapproval the loudest thing in the room and pressures you to apologize or chase them — often when you did nothing wrong. It punishes you while letting them avoid accountability. The healthy version is different: a person who needs a break says so, and comes back.
Taking time to cool down is healthy — and it's announced: 'I need an hour, then let's talk.' Stonewalling is open-ended silence used as leverage, designed to make you anxious enough to give in.
Humans are wired to find social rejection painful. The silence trains you to prevent it — by self-silencing, over-apologizing, and walking on eggshells.
You don't have to chase. You can state that you're willing to talk when they are, then turn your attention back to your own life rather than waiting by the phone.