This is a little late for the original post but may be helpful for someone else.
I had expirienced alot of the same things seen in this post. There is one additional repair step I took.
I ended up taking my radiator out of the vehicle and had it rotted out at a radiator repair center. After reinstalling it and making sure the air was purged from the engine cooling system, the problem went away and has not come back.
This was after replacing several thermostats and a blown head gasket.
Hope this helps someone in need!