One of the best ways to protect yourself from the pain of difficult interactions with others is through the practice of a loving-kindness meditation. Loving-kindness can be defined as non-judgmental, compassionate acceptance and awareness of ourselves and others.
When you practice a loving-kindness meditation, you should have no expectations of anything in return. This meditation is an exercise in unconditional love, something you develop through the daily meditative practice.
It can help you feel more present with others, develop more empathy, and be less reactive to the negative moods of those around you.