Resentment is a barometer telling us we need to make a change. The change can be an attitude change or taking a new action. The third eye can help with discernment. It can be easiest to start with an attitude change. However, if sustaining a more positive perspective becomes very difficult then take action.
Another way to think about this is that resentment is a stagnation like a log jam, with movement the stagnation breaks up. First try internal movement, if the log jam persists try external movement. Movement support health, growth, and well being.