What intrigues me about this poem is that it leaves the doors of interpretation open wide for the reader too. Presuming the reader knows nothing about you, that is. What is she like? If we knew that, we'd know what you were like by the sound of it. I like the idea that the person you are writing to gets to read this book, but as a reader of your poem, we will always be in the dark.
Sorry, rambling, but I hope you get my drift!
The end is very well executed: "just like me but braver" an author/character that inspires you and who you see something of yourself in but the difference comes in the fact that they are braver, which leaves the poem wide open to more interpretation about your self confidence, self image etc. That little pause ."...but braver" is very effective.