I've been on plenty of lads holidays, but the year before last it was just me and 1 other mate as everyone else was gay. Had a fucking awesome time in Bulgaria. Plenty of Russian chicks
Point is, it doesn't really matter where you go or the fact you're only going with one other. What matters is it's what you make of it, as long as there's good weather and good nightlife what are you worried about?
More people doesn't necessarily mean more fun.