Everyone has different pieces of their life. Some parts, more separate than others. There's work, friend groups, significant others, family. Sometimes multiple groups of some. You don't always act the same or say the same thing with each group. You might not say the same comments or jokes in front of your friends as you might your family or your coworkers. At least, not all the crass jokes that come to my mind. You might not even say the same types of jokes with different groups of friends. Some people are able to mix these groups while others keep those pieces very separate. Whether that separation is out of desire to keep it that way or just don't know how to mix them.
People who can intermingle all parts of their life, I find mind boggling. At work you need to be a little more serious or focused with your coworkers and even more so, those you work above. With family, there's more leeway. With southern families, in my experience, you still have the level of respect and decorum. The crass stuff isn't always talked about with ones parents. Then there's your friends. The ones you make dirty jokes with or throw crude gestures at or get a little too drunk with to blow off some steam. Sometimes there's even the different friend groups where some you do that partying with and others you do the classier cultural events.
Yes, some people may be less broad in their attitudes and choice in leisure activities, but there's always something you don't share with one of the groups. It could be don't need to or just don't want to. Integrating all those parts of your life, can be stressful. Or not even make sense. Or not sure if it's possible. Do the friends you act serious and adult like with want to see you in your childish, rebellious moments that you still have? Does it make sense to still have those moments where you loose your common sense or inhibitions when you have your degree and already on your way through your next 5 year plan, maybe even 10 year? Or when you try and meet someone, how do you show them all sides of you? You want to bring them work events and not have them embarrass you, or have them hang out with your friends and not get terrified of that side of you.
Finding that balance can be even harder than finding someone or some friends in the first place. I still believe that there's a puzzle piece to be able connect as many parts of your life as you have. This can be a best friend or a love of your life. (If your lucky, both) That effort to dig through pile to find it can be daunting and quite lengthy.