1987 Cadillac Deville Water in carburetor

I have been searching all evening in hopes someone could answer a question for me. Suddenly my car has been losing coolant but was unable to locate it. It would cut out badly but no one could tell me why. I looked for leaks everywhere. Tonight when I came home I popped the hood as I saw some steam and saw coolant on top of the radiator coming out of the breather. I took the breather cover off and there was coolant all inside. I have no idea where this is coming from. I don't know if this is caused by a bad thermostat or what. It looks like it is coming from a hose connected to the breather on the back side. If someone could lead me in the right direction I would be ever so grateful.