This definition of nourish is from @merriamwebster. When it comes to relationships, friendships, food, spending habits, careers, and the various other decisions we each face, we should consider if something/ someone nourishes or hinders us.
Will _____ nourish my body?
Will _____ nourish my mind?
Will _____ nourish my spirit?
Will _____ nourish my finances?
Will _____ nourish my physical, mental, and emotional health?
Will _____ further my development?
Will _____ strengthen me?
If the answer is no, as it so often is, why continue engaging in the behavior or relationship? We know better, and we are capable of doing and choosing better.