the.com/codependency

means A relationship pattern where one person's sense of identity and worth becomes so tangled up in taking care of (or controlling) another's problems that they lose track of their own needs.

from The word grew out of addiction treatment circles in the late 20th century, where counselors noticed that the spouses and family members of alcoholics often built their whole identity around managing the addict's crises — becoming, in effect, 'co-' dependent on the same dysfunction, just from the caretaking side. 'Dependency' already had its clinical sense from substance-abuse language; prefixing 'co-' named the enabler's own hidden reliance on being needed. From there it escaped the clinic and spread into everyday pop psychology, loosening to describe almost any relationship where help curdles into control.