To add to others here, anger is neither good or bad. It is an emotion. It is okay to be angry at people causing pain and suffering. It's how you deal and use anger that matters. As others said, let it be energy to create positive change and don't allow it to burn you out from the inside.

So allow yourself to be angry, to feel the hurt and to be sad. Then do the work to make the necessary changes to make the world better.

Hugs