I blogged about this earlier, but it bears repeating. Do I use obscenity liberally in my day-to-day speech? No. Do I consider obscenity objectionable? Most of the time, but it depends on the situation or context. If I hit my finger with a hammer, I will guarantee you that I will utter an obscenity. (So too will most, if not all, of the pastors I know.)
There is a key phrase I used, and it concerns the use of obscenity in the novels I write: It depends on the situation or context. Now, I have never had a character hit his or her finger with a hammer, so the use of an obscenity in that situation has been a non-issue. I do, however, have a detective who litters the literary landscape with f-bombs. My antagonist does, too, usually when he is frustrated by the way events are unfolding.
Why do I do that?
Because that is the way life is, and I want my characters to be lifelike and exist within lifelike situations. I don't think there are many places of work where you don't hear a few obscenities during the course of a normal day. I work in a newspaper newsroom, and, trust me, there are more than a few obscenities uttered every day. Many of those are uttered by people who have a great love for the English language. But newsrooms are populated by people who face intense deadlines daily, face situations that can be quite trying as far as subject matter they cover, and almost every journalist develops a hard shell because of the nature of their work. "Hell" and "damn" are the tamest words you will hear in a newsroom.
(I will include a quick aside here. That "comfort zone" with hearing obscenity in a newsroom can be tested. I worked with a photo editor who not only would have made a sailor blush but probably would have caused Satan to say, "Did I hear what I think I just heard?" The photo editor was a walking Merriam-Webster's of obscenity. The thing that was objectionable to me was that there was no context to the swearing. It was an almost constant barrage. References to coitus, scatology, parts of the human anatomy, disdain for the focus of certain religions, etc., were all part of the daily, minute-by-minute language used. It was overused, and it became tiresome and bothersome in a hurry.)
For every character in my novels who swears there is a counterbalance of someone who doesn't. Another lawman who works with the detective regards obscenity as objectionable, and he points that out to the detective. My antagonist is balanced by my protagonist (who has several major flaws in his nature, but use of profanity isn't one of them). I have a woman who uses a few obscenities, but there is nothing out of kilter in that. Some of the choicest obscenities I hear are from that gender that is rumored to be so nurturing by its very nature. Yeah, well, there is the ideal and there is the reality. So it goes.
My point is simple: People swear, it is a part of life. I will use that if it fits a character or situation. It doesn't constitute my endorsement of it. It doesn't mean I am comfortable with it. I also am not comfortable with murder, but I use murder in my novels. I am not comfortable with violence, but I use violence in my novels.
I write about life, with its high and low points. Obscenity is just part of that landscape.