I think the key phrase is "Our culture is very sexually liberated
in the media" (my italics)
The problems arise because there is a different degree of sexual liberation in the media than in 'the real world'.
Those who aspire to the levels of sexuality they see in the media find that they come across other problems - disease, emotional complications, or simply not being able to "get it" as much or with people as good-looking as the people they see as role models.
And there are many others who think that we should not aspire to the levels of sexuality we see in the media, and that the media should not portray so much stuff of sexual nature.
What I find interesting is the different attitude to these issues in different countries. The USA seems to place a great deal more emphasis on limiting access to sex in the mainstream media - while at the same time it has phenomenally huge production of and appetites for pornography. It is a federal offence to swear on network television at any time of day or night there. And most of your TV drama output involves murder and violence, usually gun-related, in one way or another, without drawing the same levels of controversy. (That's not to say anything about it's quality, which is often very high.)
This contrasts with the UK, where mainstream TV has been happy for limited use of male and female nudity and depictions of simulated sex after a 9.00pm "watershed". You can also say the "F" word on mainstream network TV here, and even the (GASP) "C" word, within certain guidelines. They still attract their share of complaints, and our TV dramas involve almost as many murder mysteries and police procedurals. We now even have the right to see "hardcore" pornography in the same ways you do - on cable & satellite, VHS and DVD, and in print, but not on network TV. But the attitude to violence here is somewhat less liberal. These days most American TV or movie imports are edited to remove the most violent scenes, if they are edited for anything. We don't see clumsy dubbing of "muddyfunster" nealry as often as I suspect you do.
The British are still uptight about sex and sexuality, compared to the French or Italians (that have nudity in some of their family gameshows!), and of course the Germans (who ust take it all very seriously

) yet we do seem relatively more relaxed than Americans.
You don’t often see that kind of hardware on a European beach.True, but you are more likely to see unfettered, naked, but non-augmented breasts, or even full nudity, on public beaches in Europe than in the USA. Plastic surgery is catching on quickly in Europe, but perhaps the need for such superstimulation is less intense, because you can see pretty much anything anatomical you want to see.
I think this goes towards your idea of what might constitute a healthy attitude to sex and sexuality - if it were less channelled into innuendo and ghettoised into porn, perhaps Americans could stop worrying about it so much. In other words, perhaps the American media needs to be MORE sexualised, not less, but in more direct ways.
I'm not trying to bash America here, as many of the problems you refer to are equally prominent here. For instance we just got some scary figures for the increasing rates of sexually transmitted diseases, and we have some of the highest teen pregnancy rates anywhere (after you guys, that is).