Annabelle believes that gordon has committed a relational transgression, but gordon insists that he has "done nothing wrong" and that annabelle is "making something out of nothing." gordon’s is using the strategy called

Denial strategy

Explanation:

Denial strategy is the method through which a person tends to escape or distract the real fact which is put on them.These facts can be painful and harsh for him/her.They tend to use this method as defense mechanism to reduce their sadness, stress of tension and deal with the real fact in this manner so that they don't have to face it.

According to the situation in question, Gordon is using the method of denial. He is defensing himself through escaping the fact mentioned by Annabelle and instead placing the blame on thinking style and behavior of her.Thus, Gordon is denying the blame put on him.