I didn't want any flowers, I only wanted To lie with my hands turned up and be utterly empty. (29-30)
The speaker's problem isn't that she's alone: it's that she doesn't feel alone enough. But for Pete's sake lady, whoever gave you those flowers was only trying to be nice!
They concentrate my attention, that was happy Playing and resting without committing itself. (55-56)
Oh, so that's the problem with the tulips: they give the speaker's mind something on which to focus. They force her to pay attention to her surroundings. The things that tie us to the world give our lives meaning, but they also hold us down, and this is a woman who definitely doesn't want to be tied down.