There was an interesting progression of poor self esteem to confidence in your speaker. The emotion does come through. The parallelism and repetition in the stanzas was a good choice. What might make the sentiment more powerful is to be more specific and provide more insights into the relationship. The 3rd stanza is the most compelling stanza. Perhaps a poem focused on that particular part of the relationship and show more detailed glimpses into that particular slice of life would be more compelling than a overly general angst ridden view of an entire relationship and change of one's life. It was just too ambitious by half. Please keep working on it.