My dad swore like a sailor (which of course he had been), but for some reason I never really took noticed of it as a kid, and it never really rubbed off on me.
I can recall being shocked as a little tike when my friend Theresa would say "my god," when I felt it was not proper, and I was always trying to get her to say "my gosh" instead.
Even now I am much more likely to say "my gosh," "shoot," "darn it," "son of a gun" or the even the more shocking "gosh dang it." But now and then I do let the F-bomb out accidently, or even worse, "sh*t, which is a word I detest, but sometimes it just happens.
I do not think I have ever uttered the "C" word. It is far too unseemly. And I would never use a curse word to cut someone down. It just seems so wrong to me.