12/03/2013 12:10 pm ET Updated Feb 02, 2014

7 Things a Sex Therapist Says You Must Know Before Tying the Knot

When people fall in love, they usually want to jump in and make the marriage commitment. They generally believe wholeheartedly that what they feel now will never change and they don't anticipate what will happen after a few years of marriage.

As sex and relationship therapists, we think that there are some things you absolutely must know before taking the leap, so you won't be so surprised when the realities of marriage are upon you!

1) People change. People continue to grow and change throughout their lives. For your relationship to be healthy, you have to make room for changes in your and your partner's needs and feelings. Relationships can be sustainable if you don't try to hold your partner to being exactly the person they were when you married them, but instead make lots of room for them to share who they are now.

2) You can't just "go back to the way it was before." The later years of a relationship will be different from that honeymoon period you had when you first met. The beginning of a healthy relationship is generally full of uncertainty and desire, with lots of passion and learning about the other person. Later on, healthy relationships become more about stability and comfort, and sex needs to be cultivated instead of assuming it will happen spontaneously. Hoping your relationship will be the same as it was in the beginning will only make you miserable.

3) You can't "make a relationship work." We've heard many people say they are trying to "make their relationship work," which generally means that they are buckling down and trying to stay in a relationship that isn't working without acknowledging or sharing their feelings of frustration, changing needs, and/or emotional pain with their partner. Instead of trying to make it work, what you can do is be honest about your needs and feelings and understand your partners needs and feelings. You can also take responsibility for the things you are doing in your relationship that lead to disconnection and agree that you are each committed to changing negative habits and healing.

4) Not everyone will be monogamous throughout the course of a relationship. Twenty-two percent of married men and 14 percent of married women admit to having had an affair during the course of their marriage. Some couples negotiate non-monogamous agreements. Even if you think you and your partner will never desire anyone else again, it is very important to have an agreement to talk about your feelings and desires for other people so you don't end up with lying and secret affairs. The more honesty, receptivity and acceptance you bring to the conversation, the less likely it is for deception to happen.

5) Most relationships are over-compromised. Because people are all afraid of being alone, being left, or being judged, they focus more on staying together and making their partner happy then being true to themselves. The problem with this is that most people have a drive inside of them that continues to push towards being true to themselves and living the life they really want. When people compromise too much in order to stay together, they lose themselves, but the drive to be true to themselves is still there. This over-compromising leads to many mid-life crises, affairs and breakups because people feel they need to leave or be with someone else in order to get themselves back. The promise that creates sustainability in relationships is not "I will never leave you," it is, "I will be true to myself in this relationship and accept you for who you are so that neither of us will want to leave." Agree to only make compromises that allow you to continue to be yourself and to work to accept your partner's differences instead of trying to make them change for you.

6) Fighting fair is key to a joyful marriage. Blaming, shaming, interrogating, judging, and accusing are not conducive to intimacy and sustainability in relationships. Before getting married, agree on the way you want to communicate with one another around challenging topics. If you haven't learned an approach that works, the time to learn is now, before you tie the knot.

7) No one is 100 percent of what you want them to be. All relationships include disappointment. Instead of trying to avoid disappointment, agree to make room for it. Allow your partner to talk about their feelings of disappointment, even if it is something that cannot be fixed. Not every problem in a relationship is fixable, however love can survive disappointment.