Hmm, that means you're getting anti-freeze in the engine. I'm not sure where to go from here. Head gasket could be bad, cracked block. However, you have to figure out the root cause of all this. What about the oil separator. Did you just change it now or before?

Did you check for leaks (oil/anti-freeze) on the engine itself or on the floor/ground?

Again, someone else will probably have some better ideas. If you're not handy with cars/engines then you probably will want to take it to a mechanic anyways.