USEFUL STRATEGIES TO DEAL WITH DIFFICULT PEOPLE part 3
Rather than harp on what you cannot change, focus on the actionable steps you can take to forward yourself in the situation. Another thing can be ignoring. If you already have tried everything and the person is still not being receptive, the best way might be just ignored. Get on your daily tasks and interface with the person only when needed. If you are in some kind of problem necessarily escalate to a higher authority when all else fails escalate to a manager