One of the reasons for the breakdown of a relationship is adultry. Dr. Janne Lomasky states the following reasons as to why some people cheat:
1. Lack of attention and intimacy: people need and desire intimacy, physical touch, and emotional attention. When such is not received from one’s significant, one will seek it from others.
2. Revenge: people who have been cheated on may cheat in retaliation.
3. Low self-esteem: When one feels insecure about her/himself, they may have a need to seek validation from others.
4. Feeling under-appreciated:Â if one does not feel appreciated, they may look elsewhere to feel appreciated.
http://divorcedmoms.com/articles/the-top-8-reasons-women-cheat-this-may-surprise-you-2