That is a valid point. Everyone's experience is different. But Nora felt so hollow to me as a character. There wasn't anything else to her. She didn't feel like a real person to me. The ending bothered me too, that all you need to feel better is to realise that you should be happy with what you have. That the life you're in now (or her "root" life) is the best one. You can help yourself in lots of ways to manage depression, but it's s an illness, not a state of mind that can be shifted with meaningless motivational quotes.