You forgive once in a moment and then again every time the memory knocks. That’s normal.

Letting something go gets treated as a single event, which is why people assume it failed when the anger comes back. The decision happens once. Standing by it happens repeatedly, often at inconvenient hours, whenever the memory turns up uninvited. Feeling the sting a second or a tenth time is not evidence that you never meant it.

Next time the memory arrives, notice that you have a choice in that moment rather than a verdict on the first one. You do not have to argue with it or win anything. Remind yourself that you already decided, then go do the next thing on your list.