You definetly have a hydraulic system problem. I would check up under the dash and see if the slave cylinder is leaking. The way your describing bleeding the brakes doesn't really sound like a good idea. You have to be careful because you can draw air back up thru the bleed screw which is contradictory to what you are trying to do. For do it yourself bleeding one of the Mityvac type bleeders are worth the money. I think they are only like $30 from Harbor Freight. You can make your own easily if you have a hand vacuum pump.