Well, All I know here is that пусть is considered "let". I've seen it described as a third person imperative(second person being the normal,"Говори","Смотрите") . I believe4 uses this. The song lyric: "...Пусть горит любовь...", which I believe translates somewhere along the lines of "Let love burn.". As far as "Let me.." there's probably some verb that is commonly used there... or like 4 different verbs...