Does this happen to every parent?

As my kids are approaching adulthood I feel like they are slipping away.
When did they know everything? Why don't they need me?
Is it possible to have a conversation without a tendency to freak out? On their end of course...lol...
Will I ever get that sweet child back? Or shall I just sit back and enjoy the ride because.... its a thrill every day.

By nature, I will admit, I am a control freak. This is something I have had to work on, on a daily basis.
I find myself having to step back before I state my case. Trying and pulling myself together in my mind saying.".this is none of my business, stay out of it" Sometimes this works other times, out come the flood gates and I am regretting everything I just said. Because of my nature, I have worked hard thus far to parent my children in an environment that they have made their own choices about most things. It started with food as a Toddler..saying, "would you like a banana? or apples?"and moved onto putting food in the refrigerator that they can choose on their own at their eye level and height, so they could reach and get it on their own. I even let them choose their own clothes, and stopped myself from saying anything when they arrived in front of me with a variety of mismatched outfits.
 My mother had taught me that it is important to know how to do things and get things done.She had pounded into our brain growing up that if something was to happen to her, she wanted us to be able to survive on our own.

My goal always was for my children to be self sufficient. They have known how to make their own lunches since they were 3 years old. Laundry and dishes since they were 5, and been able to make decisions on their own from the time they could speak.
Its all finally came to be seen. If anyone knows my children, they are very self sufficient and well...very strong personalities and  minor control freaks. Could giving them choices as young children lead to this?
Or is it just hereditary?
I know that its not necessarily a bad thing. I want them to all be able to get by in the world and not let anyone step on them. I think I hopefully and probably have accomplished this.

Right now though, oh my...everyday is interesting. Up and down.
I can't imagine a textbook with the perfect formula. Every child is different.
I know there are people that have written books with advice and  knowledge on how to hurdle the daily drama of living with teens, but has their method really worked?  The most interesting thing is that there has been scientific research done that explains the teenage mind. I put this excerpt from a website I just found.
(see below).

 http://www.responsible-kids.net/insideteenagebrain.html

Recent research on the human brain provides parents with shocking new evidence to possibly explain the sometimes irrational, illogical and impulsive behavior of teenagers. Brain researchers can now scan the live teenage brain to observe and examine why these curious and perplexing creatures make so many impulsive and egocentric decisions, that may even sometimes lead to risky behavior.

As it turns out, brain development during the teenage years is radically more active and dynamic than previously thought. During these years, the part of the brain that requires a person to make responsible decisions, understand consequences, and process problem-solving is under heavy construction, and much of the time dysfunctional. Even though the brain is almost physically mature, the grey matter in the thinking part of the brain (pre-frontal cortex) is still making connections. So teenagers are left with most of the information reaching their brains being processed in the emotional part (limbic system).

Information processed in the limbic system, without benefit of higher level processing in the pre-frontal cortex, may result in impulsive, egocentric, and maybe even risky, behavior. Because of this ongoing construction in the thinking part of the brain, a teenager is, many times, not capable of fully processing information that is necessary to make responsible decisions. Combine this brain challenge with a teen's temperament, maturity level, developmental stage and environmental impact, and it begins to become understandable why parents may find this time so exhausting and frustrating.

...They said it all.....I rest my case.