Emotional incest is not sexual unlike the name can suggest. It's also called covert incest. It is when an adult's (parent/guardian) relationship with their child is too adult-like. The child is burdened with adult emotional responsibility. It is considered abused.
People often wonder what's SO wrong with it, and often debate if it is *really* abuse. It is considered so because it forces children to put their parent's needs first and abandon their own emotional needs and it forces them to be adults and abandon regular growth/development.
Parents that depend on children in this way are often lonely. Either from social withdrawal, singleness or a tumultuous relationship(s). Their social/support system is not great and so they lean on in-house support from their child/children.
Emotional incest can be tricky to recognise because children sometimes like it, it can make them feel very special, powerful, helpful and grown-up for their age. It can also appear really loving from the outside looking in.
Forms that emotional incest take place:
Asking children to mediate in their parent's relationship is one way in which it takes place. Children should not have to offer emotional support for romantic and social woes and be in positions of responsibility in regards to adult interactions.