When your wife isn't interested in getting busy, it's all too easy to assume she's not interested in you anymore, either.
But don't jump to conclusions or give up on your sex life just yet, said Tammy Nelson, a sexologist and the author of Getting the Sex You Want.
"You might stop initiating sex out of fear of rejection but if you want to get the sparks flying again, it might be up to you to try," she told HuffPost.
Below, Nelson and other sex experts share some of the emotional and physical reasons your wife may be distant -- and what you can do to increase intimacy again.
1. She's dissatisfied with the relationship.
For many women, sexual desire is directly linked to how they're feeling about the relationship. If your wife is annoyed with you or otherwise dissatisfied with the marriage, having sex may be the furthest thing from her mind, said Susan Krauss Whitbourne, a psychologist who writes Psychology Today's “Fulfillment At Any Age" blog.
"You need to ask your partner to find out what she's thinking," Krauss Whitbourne said. "She might point out something as insignificant as one of your annoying household or grooming habits -- or she might share a larger issue, like a problem with mutual respect or communication."
2. Sex may be painful for her.
With age comes wisdom... but also considerably more hiccups in the bedroom. If sex is painful or uncomfortable for your wife, it makes sense that intimacy has gotten the short shrift, said Elizabeth McGrath, a sex therapist and educator who works in the Bay Area.
"Both women and men experience physical and hormonal fluctuations," she said. "For women, such fluctuations might impact sexual drive along with things like physical readiness for sex, changes in vaginal wetness and simply 'feeling sexy.'"
If that's the case, McGrath said one of the best things you can do is remind your spouse you're still attracted to her, find out when she feels most relaxed and explore new options like lubricant.
McGrath also said to remember to take things slow: "Women have a sexual arousal period that is longer than men so when sex goes too fast from one thing to the next it can be hard to get turned on with the same speed."
3. You're letting days go by without touching.
Sex is about so much more than just, well, sex. It's the slow buildup, the kiss you exchange at the beginning of the day. It's prioritizing touch to show your spouse the attraction is as strong as ever, Nelson said.
"Focus on physical touch and affection every day and don’t jump into sex too fast," she advised. "Sit next to her on the couch. Hold her hand. Rub her neck. Don’t make her think that you only want to touch her to have sex."
4. She's utterly exhausted.
"Not tonight, honey, I'm too tired" sometimes really does just mean "not tonight, honey, I'm way too tired." After a busy day of work, school drop-offs and household errands, it's very likely that your spouse is too exhausted to even think about having sex, said McGrath.
"Exhaustion is real; women need a chance to feel 'full' energetically and nourished," she said. "If your partner has no time for herself or room to rest, relax and recharge her batteries, it can be difficult to give sexually."
To remedy this, give each other some alone time and "experiment with how intimacy feels after she's had some time just for her," McGrath said.
5. She's grown a little bored with you.
Years ago, sex researchers William Masters and Virginia Johnson suggested that all that's necessary to maintain a satisfying sex life as we get older is "reasonably good health and an interested and interesting partner."
Ask yourself: When your spouse looks at you today, does she still see the interesting, compelling guy she fell in love with -- or have you lost some of your luster?
"Even if you're far younger than the people Masters and Johnson were referring to, it's possible that you have lost some of your former edge," said Krauss Whitbourne.
To "get back some of what made you alluring in the first place," explore your personal interests and reconnect with the person you are outside of your marriage, she said.
6. Sex has become routine.
Over time, your sex life may have gone from hot to humdrum. If you or your wife feel that sex has become too predictable -- same time, same place, same positions -- it may be time to mix things up, said Dawn Michael, an author and sexologist.
"Change the scene, make the bedroom sexy and romantic by adding candles and soft music -- really set the stage for romance," she said. "Use your imagination to role play with each other. Most of all have fun; it's OK to giggle and tease each other. Allowing yourself to let go and enjoy the moment and the person you're sharing it with can be intimate and sexy."
7. She's not feeling emotionally connected.
Instead of dwelling on your lackluster sex life, focus a little more on the emotional connection you share with your wife, Nelson said.
"Sometimes, feeling emotionally connected helps women to feel turned on before they have sex. And guess what? This is true for men, too," she said. "Try sharing with each other three things you appreciate about your relationship. Repeat it back so you are sure you got it before moving on to the next one."
Then, Nelson recommends expanding the conversation by quizzing each other about the three things you enjoy about having sex.
"By the time you are through with this simple exercise, you'll feel emotionally connected and you might think about what brought you together in the first place," she said. "You might even feel turned on enough to start something sexy."
More From HuffPost:
Are you ready to start taking better care of yourself? Sign up for our newsletter and join our Look Good, Feel Good challenge to supercharge your beauty and grooming routine and develop healthy habits. We’ll deliver tips, challenges and advice to your inbox every day.