Love is treated here as a disease. The speaker describes catching it from another person, and it spreads through the heart, the mind and the blood until nothing is left untouched. The doctors can offer no cure, and the line "it's too far gone I'm sorry there's nothing we can do" feels flat and final, the way hospital bad news often does.
The poem then shifts. The machine goes flat, which suggests the speaker has died, and the focus moves to the person they loved. That person's face drains of colour, and the poem hints that they turn to the dead speaker's face. The wording of the opening comes back, now applied to them: realisation "infested" their mind, and guilt grew around their body. The last line, "You are bow the host," seems to contain a typo, probably meaning "now." The mirrored language suggests the speaker's suffering has passed to the other person as guilt. The mood is bleak, clinical and quietly accusing, with a sense that love can wound both people.