Infidelity is a concept whose scope depends on the couple itself. Certain behaviors may be considered more or less harmful to the relationship as interpreted by each person. For this reason there are sometimes those who fall into behaviors that can be considered infidelity even without knowing it. If the conditions of the couple contract are not clear, there are likely to be problems.
The truth is that infidelity is a hoax that hurts and breaks trust. The way in which this betrayal occurs is that which has no universally established limits. And in most cases, the couple and even those who are already married have not specifically talked about these limits. All have the conception that they are over-understood which are the behaviors that are not acceptable. And this is the main error that results from misunderstandings. The couple can interpret them as infidelity.
For some, a simple telephone message can mean an act of infidelity. While others only understand as a deception to a sexual act with a third party. This could mark hundreds of situations in which there is no connection in the thinking of the participants.
You can find different types of behaviors that for some fall into the group of "infidelities". Each person can analyze what suits their thinking. And dialog with your love to check if they agree is a good idea to start. Surely avoid future discussions.
@cervantes