Why do liberals think they know what's best for you?

So I got this message from this guy I knew from high school (I'm almost 25)....and he sent me what one guy said of my views. Basically he (white liberal) was ripping on me for being Conservative and wanting tax cuts for rich white people. And he added I'd probably never get into top bracket, and it was foolish of me to vote against my best interests. I have issues with both parties......progressives and the Republican party. I'm more of a Ron Paul type because he wants to get rid of the gold standard, federal reserve, and cut spending like crazy. So why do liberals tell me this all the time......and why would they bring up the fact that I'm in favor of rich white guys......rather than myself (I'm in favor of the greater good for the greater number). He's insuinating that I'm a middle class minority, and voting conservative/libertarian is against my best interest.