Long distance relationship - fail?

This isn't about me, but there's this 17 y'old girl who got involved with a 20'ish or something guy because he was very alike an ex of hers she loved and lost when he passed away. He's in college in another country. This means they'll only manage to actually see eachother during school breaks & holidays. Even so, he might spend some holidays with relatives and such.
Plus, at his age, he's prolly used to and expecting sex, which I honestly doubt he'll get from her, because as far as I know, and I think I know her very well, she's saving herself for 'that special someone'.
They only know eachother for less than 2 weeks.
In my eyes, this is just waiting to fall apart. What do you think?

Naah,he will make her belive he loves her, she`ll have sex with him and THEN it will fall apart. He still have chance to pork her,even a big one.

I guess you're right... I mean what are the chances for her to be really smart about this and/or him to be a really nice guy without any interests? Close to 0 at this point.

whatever you believe, so it shall be true

So.. she went on how wonderful and good-looking I am and kissed me. You should've seen her face when I bit her.. like a kid opening their Christmas present.
But, she loves him and wants to leave that as a one-time thing. So if my looks beat her love for him, that means she's pretty shallow, right?