Who am I?

I'm my husband's wife.
I'm my daughter's mother.
I'm my parents' daugher.
I'm my brother's sister.
I am a student.
I am an employee.
I am 5 feet 10 inches tall.
I weigh a bit more than I like.

And the list goes on. I have no difficulty defining myself by others and by external factors, but lately I've been thinking a lot about who I am. My true self, so to speak. After my daughter was born, I've been struggling with a postpartum depression, and it has shaken me. Though things are looking up and I'm feeling more than "myself" than I have for nearly two years, I still don't know who or what that "myself" is. It's all very philosophical, I know. And I'll probably never truly find out. But it is an interesting journey.