Just let go and don't think about her ...' What's the name of this song?

Supplement: Who do you belong to and who are you crying for? You said you didn't need comfort or company. Who is distressed and who vows no regrets? Let go. Forget about her. There are many people who love you in this world. Forget about her. Let go. Don't think about whether she deserves your concern. Let go. Why must we fight? Don't think that she treats everything as a joke. Who are you and who are you crying for? Tears, you said you didn't need comfort or company. Who is she? Who is distressed and for whom? But the result is like falling flowers in the wind. Let go. Forget about her. There are many people who love you. Let go. Forget about her. Forget about her. Why is she struggling? Let go. Forget about her. There are many people who love you. Let go. If she deserves your concern, let her go. Just don't think she loved. Why must we fight? Let go. Don't think that she treats everything as a joke.