Before the age of 21, steady dating should be avoided. It is during these adolescent years that you learn to emotionally detach from your parents. Those who become serious in relationships during this time transfer their attachment needs from their parent/family system to their partner. This is a breeding ground for unhealthy, codependent relationships.
Even if you feel you have a great friendship with your partner, your relationship will prevent the emotional growth necessary for your development as an adult. It's not just the seriousness of the relationship that's the concern, but the inability to learn how to be emotionally independent. This is an important milestone that needs to happen at this stage of your life.
In a recent area fireside for youth held in Fremont California December 10, 2016, Elder David A. Bednar said, "You have to learn how to be alone."
If you don't learn this profound lesson while in your youth, your identity will always be associated with another person. It will become increasingly more difficult to recognize and experience true love. The "love" you experience now is attachment love — an insecure, immature love that leaves you emotionally dependent on your partner.
"The problem is, a lot of teenagers jump the gun. They think these friendship-type relationships are only for younger kids, and they plunge into romantic relationships more appropriate for young adults (people in their 20s), who are in a position to think about marriage." (Unsteady Dating)
Couples who have been married for decades who have never experienced authentic love often have no idea what it is and confuse it with the codependent love they have only known since they were teenagers. While working with them, I have helped guide them as they untangle their identities and rediscover themselves. This can be a painful, scary, and very difficult process; however, it isn't until this is accomplished that they can experience the rich, eternal love which they have always craved.
All youth should avoid serious dating. I realize this may sound like a dad thing to say, and I'll admit I didn't understand it when I was young. But avoid, avoid, avoid. If you are younger than 21 and in a serious relationship right now, I would seriously plead with you to separate from your partner and discover other friendships. But most importantly, discover yourself and learn to be good at being alone. This is the greatest key to future marital success, the one that no one ever talks about.