Remember, authors use figurative language such as metaphors or similes to paint a picture for the audience, or to get a certain point across. In this instance the author is trying to relate to the reader of the sheer power the wind possessed over the narrator's body.
Emily Dickinson in the poem "If I can stop one heart from breaking" presents her thought of having a purpose in the life. She discloses her thoughts that she would love to assist people in her life so that she may keep herself busy and occupied. Her help to other people may help her in turn by not keeping herself in 'vain'. She wants to bring some positive impact in the world through her actions and thought and this would help her in nit being 'in vain'.
Start off with dear so and so, address the topic you are talking about, how you want to fix it or love it or have suggestions, why you wanna do what you wanna do with the topic and an ending sentence followed by sincerely your name