For a long time, I've been uncomfortable with describing myself as either an introvert or an extrovert, because neither definition seems to fit.

I love talking with people. I define my life's work as being of service to others. I enjoy immensely my time with my friends and family (those whom I choose to socialize with, that is).

On the other hand, I often feel enough is enough with people and their needs. I yearn for a day when I do not need to relate to anyone else, but can dive into a book or surf the internet, unmolested by complaints, needs, requirements, judgements of others. Go for a walk, pet the cat, read a book, yes.

Neither model suits me in and of itself--when I have been with people a lot, all I want to do is be solitary and quiet for a while. When I've spent a chunk of time alone, I'm looking forward to time with my friends, and ready to go back to work.

Ah, but then there is ambiversion.

The following is from Wikipedia. Reading it was an aha! moment:

Although many people view introversion-extroversion as a dichotomy, most contemporary trait theories (e.g. the Big Five) measure levels of extroversion-introversion as part of a single, continuous dimension of personality.... Ambiversion is a term used to describe people who fall more or less directly in the middle and exhibit tendencies of both groups.... An ambivert is normally comfortable with groups and enjoys social interaction, but also relishes time alone and away from the crowd.

That description is much closer to the mark.