Sometimes when I have a problem I try to ask myself:
What is it that I am feeling? What seems to be the problem?
Once I have answered that, the next question is: Is there something I can do about this? Is it TRULY in my power and in my responsibility to change this situation?
If the answer is yes, I go further into analyzing what I need to do, but quite surprisingly often the answer is: no, there is nothing I can do to change what is happening.... and so, the hard task of letting go, is the only thing left to do.......
I hope you stop feeling anger, as you know the person who is most harmed by it is yourself