Relationships are necessary throughout your lifetime for a multitude of reasons. Dating allows you to learn about yourself and the type of person you are, both before and after being in one. It gives you a sense of what you like, what you do not like, and how to change certain habits and problems in the future.
Multiple relationships will occur throughout your lifetime in order for you to gain a range of experience within different phases of maturity. Often times, most relationships begin in middle school with a simple crush that is based entirely on texting; then it gradually progresses into high school when you are able to drive, but consists of the awkward dates and meeting the parents. Then it turns completely around in college where you are entirely independent and the ball is fully in your court.
Being in a relationship in college allows you the opportunity to see your significant other in all different sides of the spectrum. High school limits your ability to do so since you typically do not live within such close proximity. By being so close, you are able to understand the type of person that they are, how they study, their sleep schedule, how they deal with stress, what they do for themselves, all of their friends, and you truly see all the quirks come out of the type of person that they are. I often like to think it is comparable to living with your significant other when you are in college because you are given the chance to see all of aspects of their personality come out whereas you would not gain that chance in a high school relationship.
Especially in college, you become entirely responsible for your lifestyle and every aspect of it. It allows you to have the ability to wrap your relationship around that as well. The text-messages and phone calls between you and them will turn very much so into simple "Where are you?" and "When will I see you?" The overall relationship becomes simplified and unique on a day to day basis.
Throughout high school, all of the relationships seem very forced around your class schedule throughout the day. Most high schools are built around a block scheduling with certain classes at particular times limiting your ability during school to add spontaneity to your day. In college, you are given the freedom to choose class times, therefore, choosing when you are and are not available for random acts of spontaneity within your relationship. You can see your significant other in-between classes for lunch or a study break, or even an entirely random hangout, but in high school you are not given that opportunity and you are very limited.
In college, you are also a bit more mature compared to high school. The maturity comes with the fact that you are entirely independent. There is no petty drama about going and hanging out with someone of the opposite sex, potential jealousy, and the trust factor is much more established since you are at the same university. The relationship is also based in-person, as opposed to over the phone or texting. That in-person communication is crucial to the overall well-being of the relationship in the grand scheme of things.
Another reason it is a stronger relationship is the fact that that you are able to be your own person outside of the relationship. You have your set room-mates, your space, your classes, your schedule, and all of your friends. All of which are yours. And your significant other has theirs. You both can be two separate people, but are mature enough to understand the concept of being in one relationship together.