Engine freezes without overheating?

I've had this thing overheated a couple of times, but not so bad it warped the heads or couldn't be easily fixed with a new gasket. I parked it last week since white smoke was coming out of the exhaust and it started rough, meaning that coolant was probably leaking in to the gas. And the car shops were all busy so it sat without starting, for a week until I could take it in. I go out to start it, and thud! it wont start, fire, turn over or do anything except thud. Garage says it is frozen and its not cold and it hasn't overheated. That after 100k miles (it has about 190k miles) that this can randomly happen. WTF? I have a dead truck and I have no clue. There was clean oil in it, the coolant was about half full, all fluids were good. Brand new Bosch battery. Is this thing really dead?

About 6 months ago, in the dead of winter, it overheated on the expressway, but not badly. I pulled over, a policeman kindly added antifreeze, and I was off and running. Funny thing is, the antifreeze, didn't leak, although it leaked out enough for it to overheat, it stayed in when it was refilled. Finally about a month ago I took it in to have the cooling system looked at and fixed. The didnt backflush, but they did flush it a couple times with water. After I got it back, I noticed a slightly higher pitched motor noise coming from the engine, couldn't tell if it was revving higher, or something else. Then a week ago, it started with the white smoke. It was running fine otherwise, I turned off the engine without hearing any problems. And now its frozen harder than a large man can pull on the crankcase.