IMO IMO IMO!!!
When someone is trying SO hard to prove that they are unique and different... I am so dark, look at me, I am so different because of my black hair and piercings, I like dark music... if you have to explain why you are so different, then you are trying too hard to be different. There is a name for these folks... posers.
Adults who make choices to live their lives certain ways normally don't explain. They made their choices, and they accept who they are, and don't need to draw additional attention to the fact that they have different preferences/taste in music than others.
The feeling I get from EB is that she has a high school mentality/maturity level. The tone of the letters made it seem like she was really trying to impress the person she was writing to, by proving to him how "dark" she really is, to get his sympathy/respect.