Honestly, Lat, I think your outright dismissal of Mary's historical existence and your heavy degree of doubt that a girl could have given birth at a young age that is socially acceptable today but hardly unusual for the time period says as much about your personal ideological and political beliefs as it does about those held by any other person here on GC. Girls are fertile in early adolescence, and many girls that age get pregnant nowadays despite the social unaccceptability and stigma behind it in modern Western society, so it's hardly unusual for scholars to speculate that Mary was in early adolescence when she conceived, regardless of whether or not the conception was divine or not.

Your main reason to doubt her historical existence, regardless of whether or not anything "paranormal" occurred in her life, is largely rooted in the fact that you have a powerful need to deny the veracity of anything that you even remotely connect to religion, no matter what history or science may say about the phenomenon in question. And I am saying this as someone who is far from a Biblical literalist and highly sceptical about many things that are said in the Bible, as well as someone who is hardly fond of organized religions. What I am saying is that the flagrant dismissal of anything and everything that can be even remotely connected to religion simply because it's of interest to people who are religious for whatever reason is no more rational, logical, or open-minded, and every bit as political and ideological, as the opposite extremes taken by a fundamantalist Bible-thumper.

And while I am not intending to get into a pointless argument over whether or not God actually exists (in any type of form), I do think it's more than ridiculous to suggest that if a deity or group of deities actually existed, that they would automatically have a moral foundation or concerns that were identical to contemporary Western cultural mores held by mortal beings and laws written by mortal hands is beyond conceited. In other words, the suggestion that if a powerful deity existed (speaking entirely hypothetically here, mind you) that he or she would always pick a girl who was at least 18 years old to perform an act of divine conception upon sounds a lot like something someone from contemporary Western society would like the sound of, and not something that makes any rational sense. If you want to accuse people here of ideological rationalizations, then it's best to do so without engaging in the same thing yourself.