You are allowed to terminate your relationship with toxic family members. You are allowed to walk away from people who hurt you. You are allowed to be angry and selfish and unforgiving. And you don't owe anyone an explanation for taking care of you.
Narcissistic mothers teach their daughters that love is not unconditional, that it is given only when they behave in accordance with maternal expectations and whims. As adults, these daughters have difficulty overcoming feelings of inadequacy, disappointm