Gonna throw this out there re: the age gap. It's totally possible for two people to be involved with each other while both are under the age of 18 and then have one cross the threshold. My "high school sweetheart" and I had a three-year age gap but we started dating when I was 14 and he was 17. By the time we broke up, I was 16 and he was 19 (and still just graduated high school b/c he started school late), so - to me, at least - the 16, 19 age-gap isn't inherently "gross."
Just figured I'd offer a different perspective based on my actual life lol.