Not only are no two loves the same, there are no two people who are the same. Taking things one step further none of us remains the same. We're always evolving and changing based upon what we learn about ourselves and about the world in general. Both good and bad experiences help to shape our outlook.
Falling in love at age 18 will look and feel much different than falling in love at 40.
Most likely you will value different qualities in a person.
It also takes much more courage to fall in love a 2nd, 3rd or 4th time. As the old saying goes, "Once bitten, twice shy."