Translation:If you told the truth we wouldn't be here.
Airelibre has told the truth and so have you. Here is a replacement sentence that fits your far-fetched requirement. "If you weren't such a pathological liar, we wouldn't be in this situation." I.e., "If you routinely told the truth (on a regular basis, including the recent episode), we wouldn't be in this situation.
This is incorrect English for most situations (though in fringe cases it can work). Grammatically your sentence works but your sentence implies that at this exact location, telling the truth is impossible or otherwise ill-advised. You can compare it to the sentence "If you were swimming, we wouldnt be at McDonald's."
The issue is that in English there are many different ways of using the conditional, with slightly different nuances of meaning, while Hebrew doesn't have all those options. Even though the lesson notes point this out (I think - from memory), not all valid translations are accepted in the answers to the exercises. This really should be fixed.