In society we often hear people talking about how detached they feel. Feeling detached is feeling cut off from a part of life or for some people their whole life. It is not being able to gain access to feelings and thoughts. Detachment or disconnection is a defence against difficult feelings but often was tends to happen is that eventually the disconnection develops so that it defends against all feeling.
There are different ways that disconnection manifests. It can manifest in response to a trauma of some kind. In certain family dynamics expression of feeling is not experienced as tolerable so a response to that experience is a turning away from feelings that are seen as inappropriate within that dynamic.