I'm so mad at people who lean their seats back on airplanes
Why would people leaning back in their seats make you mad?
Because I can't lean back on my own seat
There is nothing wrong with leaning a seat back as long as you are considerate of who is behind you. You should be able to be comfortable on a long flight.
It's not just small to me and I'm going to post about it on facebook
It's okay to talk about your frustrations if you aren't targeting anyone aggressively. If there is a problem with the seating on your next flight, you should ask the stewardess to help and resolve your issue.