The example of anger is a good one I guess. Here "letting go" can mean "releasing" it, expressing it rather than repressing it. Not overexpressing it either, nor entertaining more than it really lasts for the sake of consistency.
If Buddhists would remember to embrace the emotions and then let them go when they have completed the task would be better, I think. Instead, too many try to deny them or let them go before they have run a natural course. The story above was, imo, just plain weird:
It is here that the heart learns the secret "that to let go is also to embrace what is true." For one Buddhist teacher who had trained for years in monastery, a painful divorce and the death of one of her children catapulted her into profound grief and a reexamination of all her years of practice.
"I became overwhelmed. I would weep for days on end, not knowing how I could live, what to do. It was a teaching that no amount of meditation could help me through. I really had to face the suffering of the world and the suffering of my own mind. In those years I finally learned the necessity of letting go, of opening to the truth no matter what."
What in the world is wrong with grief? It is a natural human emotion. It shows that we love the person that has left us. It shows that we miss them. To beat yourself up for feeling natural human emotions, as I feel this Buddhist teacher was doing, is, imo, wrong.