Many disregulated eaters don’t trust themselves, have difficulty holding onto a stable identity, and need external validation to feel okay about themselves. This may be due, in part, to their not receiving adequate mirroring as a child. Mirroring is one of the most crucial experiences we can have to build a solid, positive sense of self.
According to Wikepedia [], mirroring happens when parents mimic the infant’s expressions, vocalizations, behaviors and moods to help the infant associate the emotion he or she is feeling with the expression of it. This parental imitation validates and shows approval of the emotion the infant is experiencing. Mirroring is a key part of infant and child development.

Individuals need a sense of validation and belonging in order to establish a concept of self. Parental mirroring enables infants to develop a greater sense of self-awareness and self-control by seeing the emotion they feel reflected in the voice or facial expression of the parent. The infant develops a sense of “Oh, that’s what I’m feeling and it’s fine that I’m feeling it.” Mirroring enables infants to connect expression to emotions and vice-versa, making them feel secure in what they’re experiencing.

“Mirroring has been shown to play a critical role in the development of an infant's notion of self. The importance of mirroring suggests that infants primarily gather their social skills from their parents, and thus a household that lacks mirroring may inhibit the child's social development. Without mirroring, it may be difficult for the child to relate his or her emotions to socially learned expressions and thus have a difficult experience in expressing his or her own emotions.”

Moreover, “The inability to properly mirror other individuals may strain the child's social relationships later in life. This strain may exist because others may feel more distant from the child due to a lack of rapport, or because the child may have a difficult time feeling empathy for others without mirroring. Mirroring helps to facilitate empathy, as individuals more readily experience other people's emotions through mimicking posture and gestures. This empathy may help individuals create lasting relationships and thus excel in social situations. The action of mirroring allows individuals to believe they are more similar to another person, and perceived similarity can be the basis for creating a relationship.”

What does mirroring have to do with the eating problems? Due to a lack of adequate mirroring, you might have difficulty knowing or trusting what you feel and may chronically doubt or second-guess yourself. This leads to stress and often stress eating. Due to a lack of adequate mirroring, you might have difficulties connecting authentically to other people, which leads to inadequate intimacy and insufficient support, causing you to turn to food rather than people when you’re in distress. Due to deficient mirroring, you may experience difficulty knowing what you’re feeling and find that your emotions are a jumble. To soothe your distress, you turn to food.

One of the most critical benefits of engaging in psychotherapy is that it may be the first time you experience mirroring. It is one of the therapist’s most important jobs to mirror and validate what you’re feeling. For people who’ve never felt understood or validated, this is an extraordinary, life-changing gift. When mirroring is done over time, you become more confident about what you’re feeling and that you deserve to feel it. Mirroring enables you to then go out and find other people who can (more or less) continue to mirror you so that you feel understood and valued. This then helps you feel comfortable turning to people, rather than food, when you’re stressed or distressed.