This is going rather far afield from the original topic, but since it looks like no one else cares, I'll keep on with it.
The clothing thing is a quaint anachronism that has little to no real religious significance (other than concerns of modesty, which can be met with more 'modern' clothes just as well), but it's not really crazy in and of itself, no. As for the girl thing:
Yes, some Haredim/Ultra-Orthodox have pretty strict rules about mixing of the genders (and pretty strict dress codes for both men and women). Generally, boys and girls in these communities have effectively zero social interactions (outside of family) until they start dating. Dating is an arranged, highly formalized process whose sole purpose is to rapidly find a suitable spouse. In the most extreme cases, the couple may only meet a handful of times in highly controlled circumstances before their wedding. A much more broadly followed practice in the religious world is for boys and girls to refrain from touching each other
at all, even if they can interact socially (talking, etc.). Needless to say, I imagine this can lead to some interesting wedding nights (unfortunately, the quality of sex ed in very religious Jewish communities is poor to nonexistent, meaning that the couple might even be a bit hazy on what they're supposed to be doing).
I want to emphasize that most Jews aren't like this but it is a notable minority.