Avoid using the cold shoulder or silent treatment tool. This almost always never works and certainly does not help the situation at all. There is definitely a need to speak at some point during this situation as most people would attest to the fact that they are sincerely unsure as to why there is a negative situation in the first place. Therefore by actually taking the trouble to communicate clearly and effectively, both parties will be privy to the actual cause of the current ugly situation and then will be able to move forward in a productive and positive manner.
Learning how to communicate with respect for each other is another very important element to include in the communicating exercise. Making unpleasant and degrading remarks will only contribute negatively to an already unpleasant situation. Therefore in trying to get the concerns across and understood, there should be some level of dignity and respect present in the choice of words used. Trying to hurt the other party as much as possible may seem satisfactory for the movement but it is rarely a good long term solution and might even damage the relationship beyond repair.