Im right there with you dude. I have pretty much the same height and just 5 to 10 lbs heavier depending if I just got out of the shower or not.
Its our fucking metabolism...Nothing we can do or eat changes our weight. For example, last Saturday night I split a half gallon of ice cream with a friend and didnt even think twice about it. Was hungry again in 30 minutes where I proceeded to goto In-N-Out, get 2 double-double's and animal fries. By the time I went to sleep, about an hour and half later, I was hungry again. Didnt gain a fucking ounce.
Then again, I mountain bike and do yoga regularly. But even when I was a lazy fuck eating like absolute shit, I still had the same weight, just felt worse.