You can throw me in that group. I ride what many consider to be a frame that is too small. I spent 6hrs on a fit bike to come to that decision though. Most people aren't going to do that. I think a lot of people end up on frames that are too small because it is easier for a bike shop to add a longer stem and other parts than it is to replace a frame that is too big.
For the OP, I'd spend some money and get professionally fitted. You're going to have better success with someone you can work with in person than us. If you spend the $'s to get fitted you have every right to expect them to make you comfortable on your bike, or provide you with the measurements you need to purchase the right bike for you.