もちろん、「一日の終わりに」という意味でも使えます。 辞書には、 Something that you say before you give the most important fact of a situation. いろいろあったり、試したり話したりしたけど、結局これだよねっていうニュアンスです。
例えば、
A: Have you had lunch yet? B: No. I'm thinking of skipping it. A: What? You're not hungry? B: I am, but I'm on a diet. I want to lose 3 kilos. A: Skipping meals is not good, though. B: I know, but I'm kind of desperate. A: Well, at the end of the day, your health is your responsibility.
