Whenever you are writing a story, it would be stupid to avoid those curse words if a character is a swearing redneck.
There is a big problem surrounding all the writers, tho: whatever you write about, people tend to think that you write about yourself. That is why when your character is using bad words, people might think it is actually you cursing. Nothing to be done here, just carry on with what you do and keep dropping those F-bombs when you want it/need it.