You’re allowed to feel angry. You’re responsible for what you do while you feel it.

Feelings and actions sit on separate accounts. Anger arrives without being invited and does not need to be justified to anybody, including yourself, so there is nothing to apologize for in the feeling itself. What you send, say, throw or slam while the feeling is running is a different thing entirely, and that part has your name on it.

Give the feeling somewhere to go that is not a person. Walk, write it out, say it to somebody uninvolved. Then decide once the volume drops, because the choice made at full volume is rarely the one you would defend later.