@hisgoosiegirl: I agree with this.
Personally, I think it depends on how you view an engagement. I’ll be honest, when I see very young people get engaged without any set plan of a wedding other than “someday,” I can be a little judgmental. I don’t see how getting engaged is any different than dating if you are not actively planning on getting married in the next few years or at least making serious preparation for the wedding (pre-planning, saving money, reserving venues, etc.).
I am now a senior in college and my fiance and I just got engaged. When I was about the graduate high school, I had been with him for about three years, so it’ll be nearly 8 years that we’ve been together when we get married next spring.
Unless you have religious convictions coming into play, I don’t think there is any good reason to rush into engagement/marriage. Also, I am not going to assume that you are not the exception, because I was myself, but I will caution you about being so sure about a relationship at such a young age.
I am a resident assistant at a college, and many of my residents come in with long-term significant others. MANY of these couples don’t last, and some have been together as long as you and your boyfriend have. Also, out of all of the couples I knew who were engaged in high school, only one is still together, and I’m pretty sure they ended up postponing the engagement/marriage though they had initially wanted to get married because she was pregnant.
Some couples grow and change together, and some don’t. In my case, my fiance and I both grew into ourselves and became more social while continuing to have the same core values that make a couple compatible. You can be very compatible but if you do not have the same vision for a life together (kids vs. no kids, etc.), no amount of love can prevent one of you from having to compromise on something of central importance, and a lot of couples split because of this. I think that it is wise to wait until you both spend some time apart and in college before you decide to make this sort of commitment. Just because you are mature for your age does not mean that you are finished growing and changing.
However, I cannot pretend to know how you feel and you could be right about this decision.