One widely acknowledged challenge of long-term relationships is keeping the sexual spark alive. There are so many things that get in the way: careers, routines, health problems, kids and even just lack of interest. Over time, what used to be several times a week becomes maybe once or twice a week, then a few times a month until sometimes, couples aren't getting down to it at all. Ever.

And that, for one partner or the other, can be a deal-killer.

The truth is that we aren't horny teenagers forever. Many long-term partners struggle with a loss of desire or sexual drive at some point in their relationship. And that’s normal. Unfortunately, many also break up because they aren’t able to openly discuss this issue and find a solution together.

Sex is a game for two. That means if you aren't getting any, both you and your partner have to get involved in the solution. Here are some tips on what to do if the sex in you relationship dries up.

Open Up

The issue of lack of sex never goes away on its own. Keeping quiet and allowing frustration to build only makes matters worse; nothing kills the mood more than anger and silent brooding.

To avoid this vicious cycle forget about touch for a minute and start talking. You need to open up to your partner about how you feel. If lack of sex is affecting your life and your feelings for one another, you need to acknowledge it. Talking about the fact that you don’t have sex isn’t always sexy, but neither is not having sex. If you want to get back to bed, you'll have to buck up and speak up.

Of course, bringing it up isn't easy. Our sex lives tend to be a soft spot, especially when things aren't going well. We tend to react, to be hurt, or to feel attacked when our partners bring up the problem. If you're going to make the first move, choose your words carefully. Talk about how you feel. And do not, in any circumstances, accuse your partner of anything.

Say, "I feel frustrated that we don't have sex as often as we used to."

Not, "You never have sex with me anymore."

Say, "I feel sad that we aren't connecting."

Not, "Why did you stop putting out?"

Say, "I miss you."

Not, "I'm tired of how you're treating me."

See the difference? If you open a discussion you're more likely to make progress. If you blame the problem on your partner without being willing to listen to how he or she feels, you're setting yourself up to fail.

Dude, Where's My Sex Drive?

Loss of libido can happen for many reasons. It can be linked to physical illnesses, childbirth, stress or depression. It can be a side effect of medication, such as birth control or antidepressants. In other words, just because you aren't having sex doesn't mean your partner's lost interest; it might just mean his or her body isn't allowing all that sexual energy to fire up. That's why it's important to discuss your sex life, and what may have caused it to slow down.

That said, a lack of sex drive can also have roots in the relationship. How is your communication? Do you still feel attracted to each other? Was there a recent event – infidelity, breach of trust – that made one partner angry with the other? When lack of sex drive is a symptom of another problem, you'll have to deal with that before you can get back on track in the sack.

How to Get Your Sexy Back

Our bodies tend to change relatively slowly. That means that no matter what turned off your sex drive, it isn't going to turn back on like a light switch. It will take time and require work. The good news is that the work can be fun. Just know that anything is possible for two people who love each other. Here are some tips to start feeling sexy again:

Have a frank discussion about your sexual needs. Is the problem a discrepancy in desire? Does one want it more than the other, making one partner scared of disappointing or not performing?

Plan for sex. It sounds silly; after all, the myth of good sex says that it must come spontaneously. But planning a date – just like you used to do before you lived together – is a great way to build desire. You end up looking forward to this time, which makes sex more fun.

See a couples' counselor. There’s no shame in asking for help. Sometimes, you just need an outside perspective to help you figure out how to move on with your sex life. Just be sure to choose a reputable counselor with the appropriate credentials! (You can get more libido-boosting tips from our sexpert, Jessi Fischer here.)

Up the flirting game. Living together for a long time can cause two people to take each other for granted. Start looking at your partner with a new eye. Leave sexy notes in his or her briefcase. Send a hot text during lunchtime. Welcome him or her home with a deep kiss. There are many ways to reintroduce physical intimacy and sexual desire in your daily life. The trick is to keep it up! (Get more tips in Flirting: Where Subtle Meets Sexy.)

If At First You Don't Succeed ….

If you aren't having the sex life you want to have, it often seems easier to just settle and get used to it. The truth is, you won't. Sex is a basic human need, and not fulfilling this need will only lead to more tension, frustration and anger down the road.

Fortunately, the secret to keeping your sex life sexy is simple: Have faith. Have faith that your partner loves you and cares for you. Believe that he or she still wants you, even when it’s not that obvious. Know that if you had a steamy sexual connection once, you can have it again – or even for the first time. Finally, have frank and open communication, learn to listen and put in an effort. The results are totally worth it.