By Kim Olver for YourTango.com

With around 50 percent of marriages in the U.S. ending in divorce, it's important to take a look at the marriage mistakes that can lead to divorce. While researching this subject for my book, Secrets of Happy Couples, I asked happy couples what their "non-negotiables" in marriage are. One hundred couples responded about the dealbreakers in their marriages. Here is what I learned:

1. Cheating: Many respondents said that if their partner cheated on them, they would end the relationship. Although not every couple felt this way. Some respondents indicated a willingness to work through infidelity; however, many thought they could not. Even those who believe they can stay with their partner have difficulty restoring trust. The person who did the cheating may be repentant but the person who was cheated on often feels so betrayed that they can't get past it. They continue to punish their partner for the deep hurt they feel and the relationship often crumbles.

2. Dishonesty: I was interested to learn that people in relationships can have different definitions of dishonesty. Some believe that dishonesty involves only those incidents when they deliberately say things they know to be untrue, so neglecting to tell the truth is not seen as dishonesty. For others, anything that can be misleading from the truth, whether verbal or simply not expressed, is viewed as a lie. Many people in happy relationships said if their spouse lied to them, they may not be able to continue the relationship. For many, the marriage should be built on absolute trust. When that trust is abused or broken, some cannot maintain that relationship.

3. Addictions: For many, an addiction is something that cannot be forgiven, particularly if in the beginning of the relationship the addiction was not known or did not exist. Some addiction deal breakers were drug and alcohol problems, gambling or pornography. In addition to the first two concerns, addictions create trust issues. Many people felt they would not be able to count on their significant other to be consistent in his/her behavior and to put the relationship before anything else. Eventually, this would wear strongly on the foundation of one's marriage.

4. Abuse: Many people stated that if their spouse hit them, or physically or sexually abused their children, the relationship would be over. While there are many people who opt to stay in physically abusive relationships and some spouses who look the other way if their children are abused by their spouse, many people would not allow themselves or their children to be abused in that way especially by someone who promised to love them. This, again, can be boiled down to a trust issue.

5. Major changes in priorities: Major changes in priorities can cause an end in a marriage. People grow and change; sometimes they grow together in the same direction and other times they grow apart. There are other people who never change and are the same person fifty years into the marriage. What can be problematic and end relationships is when one or both partners change their priorities in ways that are unacceptable to their spouse. Some people mentioned a major change in religious beliefs and practices could strain the relationship, some people talked about putting jobs or children before the marriage and yet others complained of drastic changes in friendships or relationships with in-laws. Again, I think it comes down to trust and consistency.

When people enter into a marriage, they have the expectation that their loved one is the person they know best, someone who will always have their back. When things happen to shake that belief, it rocks the foundation of the relationship. Being able to trust, count on and predict one's spouse is paramount to a healthy, happy relationship.

To stay in touch with Kim, go to The Relationship Center and sign up for her free monthly newsletter.


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