"Use" opens with a shrug of bitterness: go ahead and use me, everyone else does. The speaker feels like a tool people pick up when it suits them, and the poem moves from that sour starting point into something more complicated. At first the speaker watches others fall into the same pattern, spotting the ones who only pretend to care and waiting for their masks to slip. Then things flip. The speaker becomes popular, and the friends seem real for once.
But the relief doesn't last. Having friends brings a new problem: if everyone around you is a skilled faker, how can you tell who is sincere? The "room of professional fakes" is a sharp image of social life as a performance. The closing question, whether it's better to live in bliss than in reality, is left hanging. The mood is guarded, weary, and suspicious, with a flat, conversational tone that makes the doubt feel honest and unresolved.