The speaker is dealing with the loneliness of being left behind by a close friend. Someone they used to spend time with now has a girlfriend, and the speaker feels pushed aside. Even a simple suggestion, like going out on the rocks, gets a conditional answer: "only if she wants to." The couple isn't much kinder, since they ride off on their "new" bikes without inviting anyone. The quotation marks around "new" suggest a bit of bitterness, as if the speaker resents how shiny and exciting everything is for the two of them.
The mood starts out hurt and quiet, then grows more desperate. The short, flat lines at the start sound like someone listing grievances. By the end, the speaker says they are suffocating, and the broken lines "I… / Can't… / Get… / Out" slow everything down, as though each word is a struggle for air. The poem leaves us with a feeling of being trapped in loneliness, with no clear way out.