D-E-T-A-C-H-E-D

Emotional detachment is feeling as though you have no emotions, positive or negative. Generally, there is still somewhat of a negative/sad emotion present, but otherwise, emotions are not felt very strongly. In this state, it can be hard to even imagine happiness.
In the first meaning, it refers to an "inability to connect" with others emotionally, as well as a means of dealing with anxiety by preventing certain situations that trigger it; it is often described as "emotional numbing" or dissociation, depersonalization or in its chronic form depersonalization disorder.