"Surely if she is old enough to have sex she is old enough to choose who it's with." But she is not old enough to have sex. The age of consent is 16, therefore at 14 she is not old enough to have sex. It doesn't matter if she's a mature 14, having sex is illegal, and arguing that she might be mature is irelevant. Where would you draw the line? 13? 12? 11?
I also disagree with the sentiment that when you have a 14 year old you just have to let them do whatever they like because the alternatives don't bear thinking about.
If a teen is going to have sex, then they will. But as parents we can be aware of what they might be doing without encouraging it. And IMO allowing teens to have sex under your roof is encouraging it. So we do it to make them safe. So what else would we rather facilitate to make safer? Allow them to do drugs at home rather than sharing needles in some back alley? Drugs are as illegal as under age sex after all...
Re the older guy, on the surface one must question why a 22 year old would be interested in a 14 year old. However it is entirely possible that the 22 year old is immature enough to be on a younger level (girls are far more mature than boys anyway, so 14 year old girl would be more at the level of an 18 year old boy and thus if 22 year old was immature the gap might not seem so huge emotionally.
When I was 14 I went out with a 19 year old. He was immature and I was mature for my age. Certainly mature enough to know that sex at such a young age was wrong, and he was religious and A didn't believe in sex before marriage, and B wouldn't have taken advantage. And while the age gap was huge, and while it wasn't until we broke up did I suddenly understand why his mother seemed so against the relationship (she was never hostile or anything - just didn't seem overly keen iyswim, although invited me to stay for weekends etc was just ve particular about doors being left open etc), he certainly wasn't with me because he wanted to take advantage. The sad (for him) fact of the matter was, he loved me. Truely he loved me, and about six months ago he told me in an email (about something entirely different) that he'd never felt about anyone the way he felt about me back then. (I hurredly backed away and have had limited contact since). but I think he would have been horrified to have been considered a pervert, just because he happened to fall in love with a girl who was that much younger than him.