Actually, throwing a 7 and beating a 2 is awful for the person throwing a 7!

The trick of the game is to always guess the number 1 higher than what your opponent will throw. In the Ace-High version* your 2 is all but an automatic loss, unless you think that you can 100% predict when your opponent is throwing their 2 in which case it has as good an odd of winning as your best card (assuming you're playing a random number generator, I suppose).

If you throw a 7 and I throw a 2, then you win the round. Whoot! but now that means that your 6-2 are vulnerable to 1 card more than mine are. My 7 becomes, in terms of cards that it can take, as valuable as your 8! Actually, more valuable since I will have another 8. Another way to look at this is that the average value of cards in my hand has gone up relative to yours. If we were to throw random cards, I have a better chance of winning.

So if you think your gf is going to throw a Jack, what should you do? If you need to win the trick, you should throw a Queen, King or Ace (but which one?!), and if you need to lose the trick you should throw your lowest card- it's almost definitely a loss anyways, and you exchange it for a very powerful card!

* (which is how I play because despite some "definitions," Ace means Awesome and always will/should)