Your family is full of retards. You need to make a point of telling them that they need to stop believing in stupid stereotypes and to grow up

The girl most likely feels inferior to him and probably wants to bring him down to her level so she can feel more confident about herself

It's not exactly normal, but not weord either. Some people do it, some dont

I have a few friends that are germaphobes. Just carry a bottle of hand sanitizer with you at all times. Try to challenge yourself with just one small bottle a day. To keep it under control