You've met the person of your dreams and decided to spend the rest of your lives together.

You think each other are greatest things since peanut butter and jelly, and you cannot keep your hands off of each other.

Several months later, you are so busy writing thank you notes and working to save for a house that you realize you haven't been between the sheets together in weeks.

Or maybe you have been married for 30 years, and you forget what intimacy even is.

Both of these things are common, said Dawn Lipthrott, a marriage and relationship educator and coach.

Lipthrott said when people first fall in love, neurochemicals such as dopamine and phenylethylamine (PEA) increase in production, which increases desire.

At some point, the chemicals go back to normal and the urge can drop off. That's when little irritations and anxieties can pop up and things may change.

It's completely normal and doesn't mean you are with the wrong person or that the person has changed, Lipthrott said.

"Chances are you could leave the relationship, get into another one and within a year or two, find yourself in the same spot," she said. "A good marriage or partnership is built by learning how to become good partners to one another."

And it doesn't mean it's time to live without sex, either.

Ditch The Sweats

One expert says many couples have it wrong. They get all dressed up go to work and then come home and throw on comfy clothes. Couples overlook looking good for each other.

Sometimes getting back in the groove can be just as simple as taking off the sweatpants, said Mort Fertel, author of Marriage Fitness.

"Ironically, we get decked on special occasions when there are 100 other people in the room," he said. "You should be doing that for each other. Your mate is the one you want to turn on."

He recommends having a date night and getting dressed up like you did the first time you went out.

Fertel also said diet and exercise are important. They improve your appearance and help your confidence by giving you more energy and overall vibrance.

"Those characteristics are seductive and make you feel more sexual, and in turn that also makes us more desirable," he said.

Lipthrott said caring about your appearance enhances your sexuality, both for your partner and for you.

"Sometimes a person's sexual life suffers because they are embarrassed about their own body," she said. "For both men and women sight, smell, taste, touch and sound are all part of the sexual experience, and each contributes or detracts from sexual enjoyment."

Have An Affair -- With Your Spouse

Even if you think your partner is dead sexy, it doesn't mean you'll be tearing each other's clothes off the second you walk in the door. Life gets in the way.

"Sometimes couples try to squeeze it in at 11 p.m. when one or both are exhausted," Lipthrott said.

Scheduling some bedroom time doesn't have to be boring or monotonous. Creating date nights or an occasional overnight getaway is essential, especially if you have children.

Fertel recommends couples getting a room once a month and having a baby sitter watch the children. He said the excitement of a new place and mystery can be amazing and feel exciting.

"It is a wonderful thing to have an affair with your spouse," he said.