I do this only when I've had enough of the person or feel taken advantage of... Yes it is immature and really I should just let go, but as someone with mental health issues, you only can hold in things for so long lol. E.g. My parents were hypercritical of me growing up, and nowadays I've been taking it less, blowing up at them easily for pushing my buttons, and telling them the times they screwed up as well. Probably an Fe thing more than a Fi thing...