Olive believed she had left her pain behind, but it returned with a vengeance, making her feel trapped and overwhelmed. The imagery of a railway tunnel suggests that she is caught in an emotional deadlock, similar to a train that has abruptly stopped inside it, leaving her feeling helpless and confined.

This sense of entrapment is further emphasized by the metaphor of a burrow where a creature is stuck, unable to move in any direction. Olive's experiences illustrate the struggle of dealing with past trauma and the difficulty of moving forward when burdened by intense feelings of confinement and despair.