Someone whispers "Trust me" into the night, and the speaker stops to think about what that really asks of her. Most of the poem is her turning the idea over. Trust is slow to build and can disappear in a moment. Misplaced, it can leave "broken souls" and heartache. It can be handed out freely when we're young, and taken back just as fast. Lives can depend on it, yet it is "slippery," and she admits there is "no real reason for it."
That list of warnings makes the ending land harder. After all her doubts, she simply answers "Yes," and a grin tugs at her lips. The speaker seems cautious and thoughtful, but also drawn to this person, and her smile suggests the choice feels exciting rather than fearful. The mood starts out hushed and uneasy, then turns warm and a little daring. The poem suggests that trust is never fully logical, and that she is choosing it anyway.