Distract the conversation from the drama. If he is agitated and acting out, attempt to divert his focus and energy elsewhere. Suggestions for anything else to speak about or focus on are welcome. Rather of allowing him to blame you or place the weight on you, you might try to turn the situation back on him. For example, if he gets angry when you don't give in to him then tell him that you aren't going to let him get away with it.
Dealing with a dramatic partner isn't easy but it can be done. Try not to take it personally; remember that he is not trying to hurt you.
The only way to survive or succeed with someone who is constantly putting you down is to stop caring what they think. You cannot change them so there's no point in worrying about it. Instead, concentrate on your own life and stay away from theirs. That way, even if they do have some bad habits, at least you're not involved with their problems.
If you believe the problem lies with you then you will always feel responsible for the outcome. But if you realize the problem lies with your partner then you will always have an escape route. A lot of times people look to others to make them happy but they just need to look within themselves first.
If you're dealing with someone who throws tantrums to create drama, keep your remarks to a minimum. When they perceive that you are not going to fight back, they will abandon the pattern. Offer your assistance if you observe someone who is suffering from a lack of drama. Demonstrate to them the value of tranquil periods in life.
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Five Strategies for Dealing with Dramatic People