There are two kinds of anger.
There’s the anger in the moment – that’s lizard brain, fight or flight, a threat to safety. It’s our body’s natural protection mechanism that gives us the extra energy to defend ourselves or run away. When the threat is gone, the anger subsides.
It’s sustained anger that’s the problem, and that’s what we’re usually dealing with when we’re wanting to process some anger in us. When we’re reliving anger “after the fact”, it’s just stories – that’s why anger is ALWAYS tied up with thoughts – it’s sustained by thoughts. Without the thinking, the anger goes away. Which is not to say that you can get rid of the anger just by refusing to think about it – you need to process the thinking, get clarity, work out the needs underneath it that aren’t being met, and find a way to meet them. Then you don’t need the anger any more, and it’s free to leave.