Parental Alienation Syndrome (PAS)
"This condition arises as a distinctive form of psychological injury to children in high conflict divorce. It occurs when the child becomes aligned with one parent as a result of the unjustified and/or exaggerated denigration of the other parent. This leads to an impaired relationship with the alienated (target) parent and an absolute loss of parenting as a result of the hostility of the parent producing the alienation. In most cases of high conflict divorce, there are degrees of alienation. In severe cases, the child's once love-bonded relationship with the target/rejected parent is destroyed."
(From: Rye Hospital program for Parental Alienation Symptom. This article provides information on diagnosis and treatment).