Is it possible to find your husband in high school?

My now boyfriend was my best friend for four years before we started dating this February. It's been about four months already, and I know it's not that long, but it just feels right being with him. I'm 17 and he's 15, and I know it seems young, but he's really mature for his age. He's not like anyone else I know- he's so thoughtful and caring and has a really level head on his shoulders. He's helped me through all of my tough times and we know everything there is about one another. Being in love with my best friend has been the absolute best thing that's ever happened to me. He's the only one I can spend time with day after day and never get tired of being with him. He says he could seriously see himself marrying me, and I know there's PLENTY of time for that (like, 7 years or more) but I just know that we're going to be together for a long time. I hear stories from older people how they met their husbands or wives when they were in high school and they married their highschool sweet hearts. How should I go about looking at this?