The speaker, written about as "she" and named Eli in the heading, is nearing the end of her final school year. Everyone around her seems happy, but she can't bring herself to smile. She admits she doesn't like school, yet she has become attached to it without meaning to, and some memories there are ones she loves and wishes she could return to.
What troubles her most is how easily her classmates, whom she has known since childhood, seem ready to leave without looking back. She can't do that. The poem suggests they are her only friends, so graduating means losing them. She already feels lonely every summer, but this time, the poem says, it will be "for real."
The mood is quiet, sad, and a little stuck. Short lines and repeated words like "alone" and "memories" make the ending feel heavy, as if she is left with nothing but the same old memories.