Being emotionally vacant is a defense mechanism. A child who lives in a family where both parents suffer from addiction, for example, can seem emotionally vacant which is also referred to as detachment.
I’ve met adults who are like this, too. They seem to have no feelings or they seem to skate the surface of life without ever getting into any kind of deep conversation or intimacy in a relationship. Try to ask them something more intimate than the weather and they’ll shut down.
This can be a learned behavior, a type of survival mode.
People think, if they can’t feel, they can’t be hurt. They want to numb the feelings instead of feeling feelings.
This can manifest itself in multiple ways from substance use disorder to suicide, anger, depression, cheating on a spouse, lifetime struggles with relationships and more rarely, violence directed at others.
There are a lot of emotions besides joy and happiness such as: anger, jealousy, fear, sadness, disgust, surprise, guilt and so on.
Why do we see the so many of these as personality deficits or a weakness?
No matter what your age, you can learn to express yourself and to learn to make meaningful connections. The first step is a willingness to do so.