The speaker can't escape a person who seems to be everywhere at once. The opening lines, "He's there. / He's here. / He's everywhere," are short and blunt, and they pile up like a trap closing. Then the poem moves inward, from head to mind to soul to spirit, as if this presence is working its way deeper and deeper into the speaker until nothing is left untouched.
The feeling is a mix of obsession, helplessness, and maybe fear. We don't learn who "he" is. He could be a lost love, someone controlling, or even a figure like fate itself, and that vagueness lets the unease spread. The speaker tries to get away but says flatly, "But I can't."
The ending shifts to the idea of breaking "the connection," the "line holding us to our fates." Notice the word "us": the bond goes both ways. The mood is tense and claustrophobic, with a faint sense that the speaker both wants to be free and feels it may not be possible.