Change your part of the interaction. Remember, you always have control over what you say or do. You need to prepare. Practice your strategy before confronting the person. Using a friend for role-playing and feedback is best.
Timing is important.
Select a time to confront the person when you both have ample time and energy. Choose coping techniques that are appropriate for each specific difficult behavior. For example, with a hostile or aggressive type you need to stand up for yourself without getting into a head-on fight. Monitor the progress. Sometimes, no matter what you do, your attempts at coping will not produce the desired results.