You get to have a bad mood. You don’t get to make it the family’s weather.

Having a bad day is not something you need permission for. What changes things is the spill, the way a heavy mood quietly sets the temperature for everyone who lives with you. Nobody is asking you to perform being fine. They are asking not to be treated as the cause of something they had no part in.

Try naming it at the door instead of carrying it in silently. A plain sentence about having a rough day, and that it has nothing to do with them, costs almost nothing. Then take the twenty minutes you actually need.