Anything that costs you your peace is too expensive.
This has become something of a personal statement for me as I manage my health. If a person, situation or thing is going to disrupt my peace, and in the process, my mental and physical health, IT MUST GO. It’s not easy, because sometimes that means letting go of people, things and projects you care about. But if it’s not growing you, or otherwise having a positive or beneficial impact on your life, it needs to be eliminated. Your peace is that valuable. Guard it.