How do we define ourselves?

I want to focus on how people define themselves. When you say you're a "good person" that goodness is relative to the people around you. Is it possible to define who you are separate of other people? Are we nothing more than our relationships? I chose this question because I think we define ourselves based on our personal interactions. I know that my friends and family are such a deep part of me that I would be incomplete without them. The strong relationships I have make material possessions meaningless. A few weeks ago I went to my cousin's wedding reception and being around all of my cousin I realized that I don't care what others think about me because I am loved unconditionally and these relationships give me the courage to be myself and actively participate in life. I let go and danced around crazily. I have become the person I am today because of all the people in my life. I'm funny because I make people laugh and I'm trustworthy because I'm always true to my friends. Without these relationships my characteristics have no meaning.
In the Odyssey Odysseus is clever because he outwits Polyphemus and disguises himself from the suitors. But without his interactions and circumstances what is he? Odysseus is the impact he has had on people just as he is the flesh and blood that make up his body. He is clever, proud, and strong but all because that sets him apart from other people.
The Help also has a strong focus on relationships and identity. Prejudice causes people to define one another based on race and stereotypes rather than the examples people set through their actions. Some of the characters are able to get past these generalizations and discover who they are through the way they are treating others. The maid Minny realizes that she has been so used to horrible employers she stopped viewing her employers as emotional human beings. She begins to see herself as a strong independent woman because her new employer views her that way and gives her the courage and the circumstances necessary for Minny to become strong.