Drop ink in a glass of water and it spreads everywhere. One mood in a small room does the same.

Moods are not private in close quarters. Whatever you walk in carrying reaches everyone within a few minutes, usually before a single word about it is said, and the smaller the space the faster it travels. This is not a reason to hide what you feel. It is a reason to know you are carrying it.

Before you walk into the house or the group chat or the shift, take ten seconds to name what you are bringing in. If it is heavy, say so plainly at the door rather than letting people guess. A stated mood spreads much less than an unexplained one.