My wife and I have a d/s type of lifestyle. We try to typically treat it as a private thing but occasional people do figure things out and ask questions.
Friends and people i work with are semi aware, perhaps they know the whole scope of our d/s lifestyle but i tend to think we are "old fashioned" instead. We are in our early 30's, so we arent that old.
I usually give her any directions or instructions prior to our arrival somewhere. Before we enter a restraunt or friends house she knows what is expected of her so i dont make any scenes. I personally tend to keep things between us. She is happy to serve but embarasses easily and i feel its respectful to her to not embarass her. I think d/s should be a two way street to a point, perhaps i am wrong.
Neither of us has ever been properly schooled if you will in d/s we just have always had a relationship where she is submissive to me and later i learned she is very submissive to me and after finding a few websites discovered we fit the d/s category in some respects.
Her dad was visiting and noticed the anchor points on the bed while seeing the new house. He didnt really say anything snide or rude, he just chuckled, looked at her and gave us the whatever works for you and continued his tour. He is aware she is a very submissive wife to me in how she acts and speaks to me. He treats me VERY well and never fails to send me a lavish gift for special occassions so i feel he knows but understands its her choice not something i force on her and i do spoil her and treat her exceptionally well. I never viewed her being submissive to mean she is a doormat, i think he knows that. Her mother is a whole different story.
Her mother doesnt "know" but suspects something is odd. She pretty much loathes me and i suspect it is because she sees her daughter as submissive to me and being a liberal femme-nazi type is disgusted by it. My wife grows her bikini area and underarms natural per my liking. I trim her bikini line to my taste, which means only a little bit and only during the summer months for the pool. Underarm hair is a fetish for me and hers are kept natural. Her mom has noticed this and chastised her for it several times as being un ladylike. My wife remarked i liked it and thats why so again her mom cant believe her daughter is embarassing to be seen with in public simply because her husband prefers it.
Its a slippery slope, it depends on the views the people your thinking of coming out to have. Its pretty comparable in my book to being gay. You want to be yourself and you want people in your family to understand, you want to tell them or let them know your a certain way but fear the ridicule and being shunned by those you love most. Only you will truly know how much to tell them if you should tell them at all, or let them observe it. My dad knows and of course he thinks its the coolest thing hes ever seen or heard... He wants to know where he can find him a beautiful submissive LOL.