By:   Melanie Votaw

Movies and sitcoms are filled with jokes about the boring or nonexistent sex lives of the long married, but in real life, it's no joke. 

When sexual interest starts to wane, it's far too easy for couples to ignore the problem, hope it works itself out on its own, or pretend it won't have an effect on the relationship. As long as you still love and respect each other, that should be enough, right?

Not really. 

The truth is that without physical intimacy, a couple can easily grow apart emotionally as well. One or both of you might end up feeling rejected and resentful. Then, if you avoid talking about it, the resentment can grow, making the situation worse. When sex becomes infrequent or dull in a marriage, ignoring the issue often leads to extramarital affairs.

How does it come to that? What are the most common ways couples ruin their sex lives? 

Here are the top five:

1. Not making time for sex 
If you're like a lot of couples, the demands of everyday life take precedence over sex. After all, work and children are more important than naked time … aren't they?

Well, yes and no. Of course, you can't allow carnal pleasures to cause you to neglect your job or children, but it's a slippery slope if you're always putting life's practical matters above your intimate moments together. Far too many relationships fall apart because sex ends up at the bottom of the to-do list. 

For some couples, months go by without anything more than a passing kiss or hug. Yes, you're exhausted and overextended; isn't everybody? But not creating enough balance in your life to include sex in the mix is simply a recipe for a divorce.

If you value your relationship, maintain the physical connection with one another as much as your connection around the dinner table or little Stacy's dance recital.

2. Getting stuck in patterns 
Every time you have sex, do you do it exactly (or nearly) the same way? While there's comfort in knowing what your partner likes and vice versa, that comfort only goes so far. Eventually, the complacency involved in sticking to the status quo will send you snoozing before you've achieved climax.

These patterns often develop because we're afraid of being rejected for introducing a different idea, or we're too inhibited to try something new. We've grown accustomed to "doing it" a certain way – it's always seemed to work – and we feel afraid to push the envelope or move out of the box we've crawled into.

The remedy? Decide that you're going to try something different. There's no reason to break out into some kinky area (unless you're both into it), but try something new that's reasonable, small, and not too intimidating. Even a small effort at changing it up can make a big difference.

3. Not talking about what you want 
Yes, it can be nerve-wracking to tell your partner what you'd like in bed, especially if you've avoided the discussion for years. If you've never talked during sex or given one another instructions, it may be best not to surprise your partner by suddenly becoming chatty during the act.

Instead, start by making it about pleasing your lover. You could say, "Tell me what you like. Tell me what to do next. I want to know that I'm making you feel as wonderful as possible." Then, when it's your turn, you could say, "Can I tell you what I'd like, too? It might be fun to change things up a little."

If your partner worries that your new instructions mean you haven't liked his/her lovemaking before, be reassuring. It isn't about judging the past; it's about making sex even better. And just because you want to try something new doesn't mean you have to throw everything from the past out with the bathwater.