Depression has lots of ways of manifesting.

One way of describing depression is an unwillingness to engage with life and to feel, because the person has learned that engaging or feeling will lead to pain. This is the functional contextual definition.

Another one comes from Martin Seligman, who defines it as an unwillingness to try things because the person has learned that engaging in something will lead to failure.

In either definition, the unwillingness is contextual. In other words, someone might be depressed regarding work but not their partner. Or someone might be depressed regarding their family but not their partner.