Brake Problem on 95 K1500

Hi guys, I have a 4wd 95 K1500 with ABS. I am experiencing a real spongy pedal and it seems that I eat up alot of brake fluid. I think it gets worse when the ABS kicks in. I noticed that the ABS kicks in at times when it really doesnt need to be working. This sucks and there is no air in the brake lines. I did replace the wheel speed sensors on both sides so i know it isnt that