Here's How Relationships Can Change Over Time

"Many couples, especially those in long-term relationships, report a change in desire at some point in the relationship," Howard-Blackburn says. Changes in libido are nothing to panic about, as long as you and your partner are both willing to communicate and work through the problem together.

"One person might be initiating sex more, while the other might like sex most in the mornings," Howard-Blackburn says. "Because of the different roles we transition into on a daily basis, sex stops becoming a priority. This is not a major alarm in some cases, thankfully, many couples are able to re-connect with the help of a sex therapist or counselor."

As we get older and have new sexual experiences, our sexual likes and dislikes will change, too. If you or your partner develops a new sexual interest and shares it with you, that's a sign that your sex life is healthy and open.

"We're all evolving as we grow through life," Howard-Blackburn says. "Sexuality is fluid so it's not uncommon to gain new sexual interests as a relationship progresses. Some people find that they are no longer turned on by the same actions, and now require a different type of stimulation."

Although it's OK for your sex life to evolve over time, one thing that's a major red flag is if your sexual intimacy comes to a screeching halt — with no communication or acknowledgment whatsoever.

"Abruptly stopping sexual intimacy is another abnormal or uncommon change that requires attention," Howard-Blackburn says. "This is an indicator that there is some sort of disconnect in the relationship. It is recommended to seek help immediately in instances of abuse."

Healthy couples understand that it's crucial to have independence and alone time within a relationship. Over time, you might discover that you need more/less alone time than you did early on in the relationship, but that's not a bad thing at all.

"As you get to know your partner you don't need to be around them as much," Kimberly Hershenson, LMSW, tells Bustle. "There should still be quality time spent together but it's no longer necessary to want to spend every second together."

Even during stressful or difficult moments, partners in a loving relationship are always willing to listen to and empathize with their partner's feelings. If your partner has grown less empathetic and more impatient and careless where your feelings are concerned, that's a serious red flag.

"When one can no longer put their self in a position to understand their partner's feelings, the relationship is headed for disaster, or already over," Howard-Blackburn says.

There are a lot of things that might cause a rough patch in your relationship: family issues, job loss, cheating, money struggles — the list goes on. If you're in a healthy partnership, you can work out disagreements and find solutions in a way that's fair, calm, and mature. Life isn't always fun and carefree, so don't be afraid to lean on your significant other and weather the storm together.

Every long-term couple will go through periods of stress, tension, or even anger from time to time. But if you're in a healthy partnership, you will be able to work through those conflicts calmly and maturely, with neither of you crossing boundaries or becoming abusive to your partner.

"Another abnormal change in a relationship is if a partner becomes abusive," Howard-Blackburn says. "This includes sexual, verbal, financial, physical, emotional, and/or psychological abuse. Any type of abuse in a relationship is a red flag."

Often, a controlling partner will attempt to disguise their controlling behavior by saying something like, 'I only do this because I care about you' — but it's important to be aware of what behavior is boundary-crossing and disrespectful.

"If you are told how to dress, reprimanded for your thoughts and opinions or are told who you can associate with, these are all huge red flags that you are in a toxic relationship," Hershenson says.

As you grow, it's only natural for your hobbies and friend groups to change as you develop new interests. Even if you and your partner used to share all the same hobbies, it's OK to branch out and explore your own things later in the relationship.

"Your hobbies and friendships may change over time," Stef Safran, Dating Expert and Matchmaker at Stef and the City, tells Bustle. "Once you have kids or move you may find yourself finding new friends and new hobbies to go along with your lifestyle."

Why You Shouldn't Fear Change In A Relationship

If you're with someone long-term, it's natural and healthy to grow and change as a couple. It might seem scary to think that things won't always be the way they were when you first started dating, but as long as you and your partner are willing to embrace life's ups and downs as a team, there's no reason to fear your relationship changing. "Change is inevitable," Howard-Blackburn says. "Many times when a client mentions that their partner 'changed,' it often comes from a place of resentment. We spend a lot of time focusing on the negative aspects of change instead of embracing a different journey. Why? Simple! We like familiarity. It's safe, stable, and predictable."

It might not always feel totally within your comfort zone, but ultimately, experiencing new challenges and phases of life with your partner will only bring the two of you closer — which is what serious relationships are all about.