"Never Will I Marry" by Frank Loesser from Greenwillow, 1960
Nota bene: this song has a killer jump in it. It is either a tenth or an eleventh--I can't count that high--but if you can absolutely nail it, then do it. If you cannot cleanly make the jump, skip it.
It is on the cast recording if you can find it and also on a very early Barbra album (1st, 2nd or 3rd).
The song also gives you something to sing about. If you analyze the lyric, it could be a fairly bitter song. Don't play the bitterness, play the frustration of trying to explain your predicament. As written the character is a wanderlust which is why he can't marry. Make your POV anything you want as long as it works without going overboard.
By the by, the song was written for a man, and a basically non-singing man at that, our own Norman Bates, Anthony Perkins.
"If my life weren't funny, it would just be true. And that would be unacceptable."
--Carrie Fisher