I would think that keeping 2 snakes together creates competition for food which is primary to their survival. Also they are solitary animals so keeping them together does not benefit either and they will never be buddies. More aggressive behavior would be expected. Separate then and you will likely see the behavior change when there is no competition for food. A snakes life is very simple, hunt, eat then hide and digest, repeat. They are not animals that make friends. If its smaller than you then it goes down the cake hole, if its the same size or bigger its competition. Not much more than that.