A distinguished writer of books in various forms — poetry, essay, memoir — Sarah Manguso embarks on her first novel with “Very Cold People,” a striking work about what it means to be human. She discusses how she came to be the person and writer she seems to be now, and why it was necessary to write fiction to make the kind of book about Massachusetts she wanted to make. This deeply moving novel portrays being overwhelmed by the small moments of life, and documents the experience of being a criticized child.