The person packing quietly may be feeling more than the person speaking publicly.

Feeling does not distribute itself evenly across volume. Some people handle a leaving by talking about it and some by folding things into a bag with more attention than the folding requires. Silence in a room full of goodbyes is easy to read as coolness, when it is often the opposite: the person has worked out that if they begin, they will not manage the rest of the afternoon.

If someone near you goes quiet before a change, resist filling the space with questions. Stay in the room and do something ordinary alongside them. Say one plain sentence about what they mean to you and let it sit.