Here we see the great Lea Salonga sing-speak a very emotional song from Stephen Sondheim's "A Little Night Music."
What choice does an artist have? Everyone knows it's very hard to maintain composure when you're crying that hard and the difficulty is magnified for her because she has to sing.
Watch this video. Listen to the song and allow every single repression you have to flow away with her voice. Allow your emotions to soar. When your chest starts to hurt and your eyes start to moisten, don't hold back. Just let it go. Let it all go!