Ever since the dawn of man, teens have been embarrassed by their parents. Parents are the un-coolest people who ever walked the face of the earth (unless your name is Aimee, Kelly, or Jack Osbourne, maybe) and no teen wants to be seen with his parents more than absolutely necessary.
This is age-appropriate behavior. If you saw a teenager still clinging to his mommy, you'd really think he had problems. The trick is to get your teen to want to stay in touch with you. You need to know what's going on in his/her life, for safety's sake, but you don't want them tethered to you for ever.
Such a delicate balance.
One mom I know uses a "advise but don't check" method of parenting. She tells her daughter that she can only see PG-13 and below rated movies, but mom doesn't check the ticket stubs to see which movie the daughter saw. The daughter knows what's expected of her. The mom allows her to make her own decisions. Consequences only occur if she gets "caught."
That can work with movies, but as an overall philosophy of parenting, I'm not sure I like that. My parenting is more relationship based. You can't wake up one day and start this with a teenager, however. You have to have started from wee-small.
It goes like this: My children love me, and because we have a good relationship, they don't want to disappoint me. I love them and they know it. They have expectations of me and I have expectations of them. If they go beyond the sensible boundaries I have set, they see the hurt in my face.
I don't yell or throw things - I express my disappointment, that I expected better than that out of them. Their own conscience hurts them more than my yelling.
One of the best things we have are cell phones with unlimited texting. My daughter would rather die than to be seen talking to her mother on the phone. But a quick, quiet text letting me know where she is, she's ok, what time she's coming home - how cool is that? She could be texting Lady Gaga for all her friends know.
My teens are my "friends" on Facebook, but I never "like" or comment (publicly) on anything they post. I am training them to present a good image. I speak to them if there is anything presenting an image contrary to the one they want to present. ("The next time you have a job interview, they're going to see this. Are you sure it's part of your brand?")
Whether in person or electronically, it's important to keep up with them. Start when they're small, build a relationship of love and trust, and let them keep in contact their way. Add the electronics only when they're ready and when the relationship is already established. Those lines of communication allow you to coach and guide them from adolescence to adulthood, in a language they understand.
What language are you using to talk to teens today?