It is far better to take things as they come with patience and equanimity. Karl Jung

Everyone knows it is best to roll with the tide, as energetic reactions to small things can affect an individual's wellbeing. However, if one is in the lifelong habit of overreacting, rather than being in control, that habit can be difficult to break. Meditation has helped me maintain equanimity (there are various meditation videos with music on YouTube that I have found helpful), but here are a couple of other easy practices that have also helped me.

1. Everyone has heard the expression, "in one ear, and out the other". This is especially important when your perception is that the other person is being passive-aggressive. Why react, especially internally? When you allow these things to pass through your mind, you are practicing equanimity. (Sometimes I do allow myself to visualize rolling my eyes, without actually physically doing it.) By not responding internally or externally, you are maintaining your power. The other person will notice your non-reaction, and hopefully stop trying passive-aggression with you.

Occasionally, one does need to react verbally to something contentious that has been said, When that occurs, I consciously choose the best way to respond in order to maintain my power, without overreacting. This leads to my second suggestion.

2. The best way to respond is to dispassionately look at the situation. But how to be dispassionate when someone is attacking you? When you are being misunderstood? When the person is acting crazy? When the person is trying to take advantage of you? To assess the situation dispassionately, I try to bilocate, assessing it from the point of view of a dispassionate observer rather than a participant. I picture myself looking down at the conversation from above, and respond accordingly. That may mean either curtailing an angry response, or allowing a controlled angry response. It may mean making a kind response, or even a deflection. Please remember it is OK to pause before answering while you formulate your response. I remain "up on the ceiling" throughout, reassessing each response I make. You maintain your power when you choose your words wisely. This method works, at least for me. Try it and see if it works for you.

Psychology Today has some useful input on practicing equanimity:
4 Simple Ways to Replace Hostility With Equanimity