I totally know what you mean. That's why it was just too hard to put my French into use in Belgium and my Spanish with my housemates in the Netherlands. It's just too easy and comfortable speaking in English :) If any idea about your summer comes up, I will let you know. But even if the Bulgarians you are hanging out with speak English, make yourself speak Bulgarian to them. It's a win-win - they practice English, you - BG.