In an interview, Thirteen Reasons Why author Jay Asher says, "even though Hannah admits that the decision to take her life was entirely her own, it's also important to be aware of how we treat others" (quoted in source).Good point, Jay. The choices that the people on Hannah's list make are definitely central to the story. But it turns out Hannah's choices are pretty important, too. Even when they're good choices (signing up for a poetry class and seeking help seem like smart ideas to us…), they always seem to turn out badly. But as her state of mind deteriorates toward the end of the novel, Hannah starts making choices that she knows aren't good for her. Part of the reason she kills herself might even be that she's unable to live with some of the choices she makes in the final weeks of her life.
It doesn't matter what the other characters do; it's Hannah's own choices that lead to her suicide.
Hannah doesn't give her listeners a choice: they are forced to listen to the tapes, even if they don't want to.