I feel ya b-dub. When I wasn't saved I used to cuss a lot. Now that I'm saved, I wouldn't dare get in a relationship with any woman who uses that kind of language.
It doesn't bother me too much if people use it, but not someone I'm gonna be spending quality time with. The person can say that they will work on it all they want, but it's gonna come out, and usually at the wrong time. There are so many other words to use than profanity. It really shows a lack of intelligence.
If u wanna keep the guy as a friend do that. As far as a relationship, don't waste ur time wit this one b-dub.