As we enter our teens, it's common for us to have flings and crushes. Some turn out to be fleeting while others turn into a lifelong partnership.

Some of us just click! It's not always about physical intimacy as much as it is about mental frequencies. So, is there any fixed formula for long-lasting love? How do we know that we've found "The One?"

Bright Side put together a list of signs that can help us differentiate true love from a casual fling.

14. PDA

Are public displays of affection (PDA) always justified? Is it really linked to the happiness quotient of a couple? Studies say "Yes!" It's been shown that couples who have a photo of themselves together as their profile picture on social media or who frequently tell the world about their relationship are the ones who aren't afraid to hide the love they have for each other.

13. The Kiss-tale

The way they kiss can tell if they are in love with you or not. You must have heard about the meanings of various kisses on different body parts. But, if you assess closely, you can easily tell if you both are made for each other or not. A slow and longer kiss with closed eyes is a clear indicator that your partner is deeply in love with you, even if that is not a perfect kiss.

Scientists, through a study, have proved that saliva secreted during a kiss contains hormones that can denote various romantic things.

Did you know even animals kiss? While mammals kiss by licking the face, birds tend to pat the beak when they want to kiss.

12. You text less and mean more.

With some, you tend to send innumerable texts to make them understand what you mean. And then, there are those to whom you don't need to say much. While men think that messaging more is required only when you don't want to have a face-to-face conversation, women prefer to send texts when they are upset.

In short, a couple who is in love with each other will prefer to talk rather than text. They strictly follow the minimalistic approach when it comes to messaging.

11. Your interests are similar.

It is said that opposites attract. But it's still very important to have similar interests, similar hobbies, and liking the same things to make the relationship last long. As proven by a study, we are hard-wired to desire "like-minded people."

The study said, "If you’re more alike in terms of your personalities, you’re sharing similar styles of dealing with a variety of things in life — from interacting with friends to experiencing life changes."

10. You want to share both good and bad news with your partner.

Is your partner the first person that comes to your mind when you have sudden good news to share? Are they also who you remember whenever you are feeling low? If that's the case, then you can rest assured that your partner is the one for you. This person is both someone who supports you and who can be your shoulder to cry on.

When you are compatible enough, you will find solace in talking it out with your partner in both happy and sad times. It's the feeling of comfort that lets you discuss and share everything with your partner. And, of course, you know that they will be all ears!

9. You fight sometimes.

Is fighting with your partner really bad? The truth is that it's not! In fact, couples who fight are the ones who love each other most. Fighting indicates that you don't hold any grudges or hide your dissatisfaction.

Susan Pease Gadoua, a licensed therapist with expertise in marriage and divorce, says that "If you’re in the romantic bubble and haven’t yet had a fight or disagreement, you’re probably still on your best behavior. This isn’t bad ― and, in fact, it’s supposed to happen this way ― but the truth is, you haven’t really had your relationship tested and you may still be relating on a superficial level."

By fight, we don't mean physically, of course, but certain disagreements are always present in any relationship. If you are vocal about your issues and concerns, it means you trust your partner to listen to you and to understand you. Notice it the next time you and your partner have an argument about something. Do you resolve the issue feeling more relaxed, happier, and content?

8. You encourage each other.

Compatible partners always encourage each other. Whether you are learning to bake or have decided to learn how to play a musical instrument, a loving partner will always make sure that you get a thumbs up on every little step you take. A good partner will always support you through thick and thin.

Appreciation from a loving partner is unselfish. Even if they have no clue how to bake, they will still support you during the process.

7. They look into each other's eyes.

If you think you can look into your partner's eyes for hours, know that you are deeply in love with them. The phenomenon was proved way back in 1970 by popular social psychologist Zick Rubin, wherein he conducted a study on couples in a locked room. As per the results, couples who were more in love looked into each other's eyes for a longer time as compared to those who were not as much in love.

As compared to normal couples who make eye contact 30%-60% of the time, couples who were more in love made eye contact for as much as 75% of the time. The results of the study were published in Scientific American: "They are slower to break their look away from each other when interrupted." This indicates trust, your way of giving attention, and your comfort level with your partner.

6. You can't imagine your future without them.

When you can't picture yourself with anyone else, or when you just can't imagine your life without your partner when you're older, well, that means they're the one for you. If your partner is the one with whom you can easily imagine yourself growing old and raising kids, let the feeling sink in with a smile. It is basically the feeling of "coming home" when you think of your partner that indicates your future lies beside them.

It is not easy to find such a person without whom you feel lost!

As Megan Fleming puts it, “The man or woman you marry today will not be the same person in a year, 5 years or 10 years. The happiest couples are those committed to their own respective personal growth, as well as their growth as a couple. Your relationship is a place to heal any unfinished business from childhood.”

5. You know even the most secretive things about each other.

You know all of each other's secrets. It is because you're both unable to hide anything from each other. That is the reason you know each other better than anyone else. It is a very satisfying feeling when you know that someone is out there who knows you and accepts you the way you are.

Your achievements to your embarrassments, even the intimate details are all known to your partner. It is like you just can't hold back anything without sharing it with your partner.

4. You can be yourself when you're around them.

There is no pretense when you are with your partner. Whether you are happy, sad, angry, or just feeling frustrated, you never have to fake your emotions in front of those you love. When you can truly share your true self in front of your partner, that's when you know that you are compatible.

No matter how uncomfortable or confused you may sound, if your partner loves you, they will always understand you. Even if you are sitting with each other without saying anything, you should still be able to feel the love. Even the silence between you isn't boring, and that's the level of comfort you get from being with your partner.

3. You laugh at the same jokes.

If you and your partner share the same sense of humor and like the same types of things to make you laugh and enjoy yourselves, then you're in it for the long haul. If a cheesy punchline or the most embarrassing moment causes you both to burst into laughter, you better stick with each other for the rest of your lives. A sense of humor is the essence of life.

As per a study published in The Western Journal of Communication, 75% of happy couples laugh together at least once a day. That's a pretty decent percentage, right? If you still don't agree, there is another study published in the same journal according to which 92% of married men and women credited humor as a factor that made a significant contribution to their married life. Basically, couples who laugh together, stay together.

2. You have good chemistry.

Good chemistry is essential. And it is equally difficult as you grow old in a relationship. After the honeymoon phase is over, it sounds a little weird for some couples to even look into each other's eyes. However, if you want to know why the spark should always be there in your relationship, you must know that as per a study published in the journal Society for Personality and Social Psychology, having sex at least once a week brings as much happiness to your relationship as making an extra $50,000.

It is not just about the sex, but little things that clearly show in your body language when you are with each other like holding hands, cuddling, looking into each other's eyes, playing with their hair, etc.

1. You make it work, even if that means compromising.

The fear of losing your partner kills your ego always. You just can't imagine yourself without them, and thus, you are ready to compromise. By compromising, it doesn't mean you will be begging in front of your partner. It is more about mutual trust and understanding.

Conflicts are a part of any relationship. But, if you manage to resolve an issue without doing damage to your relationship, it means you understand the importance of compromising for the sake of your relationship. After all, the relationship is always bigger than the differences. As per relationship coach and therapist Anita Chlipala, "Conflict gets a bad rap in relationships, but what makes a couple compatible is that even when they disagree, they’re able to move past their differences and come up with compromises that work for both partners."

Do you have a strong connection with your partner?