96 Prizm front brake problems!

I installed new pads, rotors, and calipers about 10k miles ago and now the car is having the same problem again. The front brakes are locking up and I can't move the car. This was the reason that I replaced everything in the first place. I replaced the fluid and proceeded to bleed all the brakes when I installed the new parts. Could it be the master cylinder? Water in the fluid freezing. When this happens if I sit for about 20 minutes with the car running they seem to work enough for the car to be able to limp home. Brrr it's cold here in MN now. Thanks

90% sure it's the rubber hoses. They often swell themselves shut with age, allowing fluid to pass under braking pressure but afterwards, there is little or no pressure available to return the fluid back from the caliper.