On the nature of cheating

A friend of mine and I got into an argument about the nature of cheating. Her basic point was that cheating is about power. It is an extension of the sexual dynamic between two people. The cheater, the power player (in her argument), has the control. They are the one trying to get the edge in the situation. She was citing Closer as a good example of what is going in an relationship when cheating is involved. I have a different take on the issue.

Cheating is a result of weakness -- weakness in the individual or weakness in the relationship. The cheater is trying to full some kind of void in their life; scared to only love one person, low-self esteem, etc. It was once explained to me by a cheater, that they were weak, selfish and cowardice in the moment that they chose to cheat. This sentiment is more consistent with my idea.

I'm struggling to see the validness of my friends argument. Yes, it is true that their are power dynamics within relationships. But I do not think that cheating is about power within that relationship. Power is about getting what you want. If you want to be with the person, you know that you are putting the relationship in jeopardy. If you want to be with the new person, starting a relationship with someone else when you are currently in a relationship is not putting your "best foot" forward. The new person first hand is seeing that you are a cheater, a person not to be trusted. They may fuck with you, but that is all that will come of that.

Even if people stay together after someone has cheated. The relationship will be forever changed. I do not see the foundation of trust still being there. If you do not have trust... I do not know why are you in a relationship with that person.