Team Builder Matchmaking Bug?

I've been playing against a lot of high elo players for some reason. I am a low elo player that plays against people who are Silver and Bronze most of the time. There is no reason that I should be playing with people who are Gold and above (unless I chose to by playing with my friends). I literally get stomped every game and that gets old after a while if you know what I mean. Is there something I did wrong? Is there anyway you guys at Riot can explain to me what's going on? It would be really nice if the creators themselves would explain how this elo business works. I thought I had an idea of how it works, but judging from the constant stompings, I don't think I do anymore. Is anyone else having this problem? Even in ranked it can get a little weird sometimes.