First of a Few

This idea could turn out to be really silly. A while back, a radio DJ did something similar to this. I think that is where I got the idea. I will be taking a cliche or a well-known saying and then making up a story that will hopefully cause you, the reader, to be able to discover the cliche to which it refers. There is a twist, however. The actual cliche will have had words rearranged, or slightly changed, causing it to appear in a humorous light. Since I don't know how else to describe this silliness, I will just begin. The first person to post the correct answer shall receive the BIG PRIZE. The big prize will consist of being named the winner.

The young lady was not what anyone would call obese. Nevertheless, every day she acted like she was too fat to appear in public. She would cause herself a lot of grief because she was so afraid that she would become ugly. She was constantly worried that she would not be able to fit into her clothes. This caused her to be unable to enjoy her life, once again proving the adage, "A ????? is a ???????? thing to ????."

There you have it. Fill in the question marks with the right letters, post your answer by quoting the cliche in quotation marks exactly right and perhaps you could be the first Big Prize winner! Hopefully, it's not too difficult. Hopefully, it's not too easy.