Brake Issue ?? My 2007 Chevy trail blazer has 34,000 mile.

What is your question?

6 cyl, two wheel drive, positive traction. I have owned it from the beginning. This Blazer has been garage kept. Here is the problem. In this past year, there are many times that the breaking behavior on this Blazer is unexplainable. Most of the time the braking works perfectly. Depresses down about half way to the floor, breaking is gentle, smooth and feels right. Other times it begins to pulsate as if I have a compromised rotor. The brake pedal is hard and doesn't travel down as normal. Sometimes the pulsating just starts while I just driving. A bumping or pulsations which I can feel in the steering wheel, brake pedal and just overall in the vehicle. There have been times when I have to "punch" the break pedal, even when I am driving at speeds of 55 miles an hour to get the pulsating to stop. It is as if something in the brakes system is not releasing and/or just starts the breaking pulsating unexplainable. The only correction has been to stop the car and restart and the pulsating problem goes away and it seems right again. I have had the brake calipers checked. They are well lubed and move freely, boots are in good condition. The behavior seemed like the ABS is trying to work for no reason at all. I was thinking that this was the problem. So, I pop out the fuse for the ABS.... This left my ABS & traction control, panel lights on and indicating the ABS is disabled. The problem still occurs from time to time. So now I'm thinking there is something wrong with the computer which governs the whole braking system. I would like to have some insight in to the possible problem. I have been to many auto service and dealerships service centers over my 45 years of driving. Just to get jerked around by folks who can't figure out a problem, and just starts to replace very expensive parts trying to eliminate the issue at a high cost to me. I can't afford this route. Just need to know what other possible reasons could cause my issue.