Communication isn't the only relationship-testing problem.
Jaris Paul

We're all familiar with the common, harmful mistakes people make in relationships: failing to communicate, having an affair or running into financial problems -- just to name a few.

But beyond the usual suspects, what other relationship-testing problems should couples be aware of? Below, marriage therapists and relationship experts share some of the most overlooked threats to a marriage.

1. Thinking honesty is always the best policy.

Yes, being transparent about how you feel is generally the best route when having one of those Big Relationship Conversations. But communicating your feelings to your partner in an aggressive or sarcastic way is not the right way to do it, said Bonnie Kennan, a Southern California-based marriage counselor.

"When partners assume they can say whatever they feel, in a completely unbridled way, they often unwittingly do great harm to their partnerships and sometimes it's irreparable damage," she said.

In other words, your "I just have to be honest about how I feel" excuse isn't going to fly. When you do catch yourself saying something overly critical, try to offset it with some positive remarks. Marital researcher John Gottman found that a ratio of 5:1 is necessary for marital health: five positive interactions for every negative interaction with your partner.

2. Buying into the idea that marriage transforms people.

Cornell University professor Karl Pillemer spent five years interviewing older couples for his book 30 Lessons for Living: Tried and True Advice from the Wisest Americans. In that time, he learned one critically important thing: It's a huge, inexcusable mistake to go into a marriage believing you can change your partner. Marriage won't solve all your relationship problems or make the two of you more compatible, he said.

"Treating your potential or current spouse as a do-it-yourself project is a recipe for failure," he said. "Take, for example, your sense of humor: What he or she thinks is funny is important because it’s one thing that is certain not to change -- and you will be stuck with it for many, many years. If his idea of high humor involves practical jokes and yours doesn’t, rest assured that you will not find the hand buzzer or the whoopee cushion more hilarious fifty years from now."

3. Believing you can change your family's opinion of your spouse.

If your partner and your parents fail to make nice before you wed, it's not likely that a bond will form after you marry, said Kennan. And it's a big mistake to believe your spouse can control his or her family and get you in their good graces, she added.

"While spouses need to stand up for each other, it is unwise to assume the family members will change their minds -- some parents will never think anyone is good enough for their child," she said. "The couple needs to be pleasant and polite with the family, while not trying to change the rigid system. This can be a big challenge if the two partners aren't willing to do the work of neutralizing it."

4. Ignoring what your partner said he wanted before you married.

When your partner tells you he or she doesn't want kids or can't wait to move out of your current state of residence, believe them. You're not likely to change their minds on the important issues once you marry, said Becky Whetstone, marriage and family therapist based in Little Rock, Arkansas.

"Maybe when you were dating, your future life-mate told you things like they wanted to move out of state or weren't that into sex," she said. "You heard these warnings, knew they were out of sync with what you wanted, but went ahead with the relationship. The reality is, you can't get them to change their mind."

5. Expecting marriage to be easy.

Repeat this to yourself before even considering walking down the aisle: Marriage is hard work -- worthwhile, valuable work but still hard work. Few engaged couples really take the time to absorb that before saying "I do," but the reality is, it's what needs to be foremost in their minds, said Pillemer.

"To stay married for life requires resilience, spirit, and discipline. It also requires an acceptance of predictable stressors and unexpected difficulties, without giving up," he said. "Like many good things in life, the immediate gain sometimes has to be sacrificed for a long-term payoff -- like winding up still in love with someone after a half century."

6. Putting your spouse on a pedestal.

You go into your marriage thinking your partner is really something special. (Otherwise, why would you say "I do"?) But idealize your spouse a little too much and you risk disappointment when you find out they're only human, said Whetstone.

"The problem with over-idealizing someone is that sooner or later you’ll realize they aren’t the infallible person you thought they were and they’ll tumble down to reality," she said.

7. Not setting boundaries on what is shared outside the relationship.

If you're an oversharer and your partner likes to keep his personal life under wraps, it doesn't bode well for the relationship, said Kennan.

"If one partner is very comfortable turning to friends and family members for support when he has a problem and the other is not, it creates a pattern where partner B is nervous about being candid and shuts down the flow of sharing," she said. "At the same time, partner A may feel stifled and lonely without a support system."

To address the issue, Kennan said couples need to anticipate this issue and set up rules for disclosure of information to people outside the marriage.

"You'll probably have to operate outside of your own comfort zone to accommodate your partner's needs and feelings," she explained.

8. Putting too much stock in the belief that opposites attract.

You're a left-leaning introvert whose ideal weekend is a good "Masterpiece Theatre" binge-fest. Your partner is an Republican-voting extrovert who loves to travel and tries to maximize each weekend. While it's nice to believe opposites attract and love conquers all (hey, it worked for Mary Matalin and James Carville!), it's a mistake to invest too deeply the idea, said Pillemer.

"I interviewed couples who've been married for years and their strongest recommendation was simple: Marry someone a lot like you," he explained. "Marriage is difficult for anyone, but it’s much easier with someone who shares your interests and background. Small differences can spice up a relationship but what has to be almost identical are core shared values on money, career goals, child-raising and sex."

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