African Chiclid - Mating or hiding from fear?

I have 2 African Chiclids in a 42 gallon tank. They have been together for over 4 years. One is orange and one is black striped (bumblebee). All of a sudden the orange one, usually the aggressive one, is hiding in a castle and wont come out for almost a month. The black one is moving the rocks on the floor and turned darker. Did the striped one become the aggressor? Or is the orange one having babies? I can't figure them out.... need help.