I feel like I was a bit like you in high school. My advice at the advanced age of 61 :-) would be to remember that you have to "practice" relationships like any other skill. No one is born being good at them, yes some people are more "naturals" just as you sound like you naturally get good grades, while other kids may have to work harder?

So, I would not get down on myself for poor social skills if I have not been in many different social situations and have not tried different things for myself but have just sort of found an accidental one friend and let that carry me to others. If you want to make friends, I would join a few groups, whether you like the subject matter or not, you may think you don't like chess or basket weaving but if you have not given it a serious try, maybe there's something in it for you; one of my favorite books in the whole world ended up being a book about weaving (I am not a weaver, and have never even tried weaving) and, analyzing it, the "ideas" it gives me, how it makes me think/feel are what I like, not the weaving, per se. That only happens if we're "moving", out-and-about I call it. Looking out the window at the weather is one thing but is not the same as being out in the weather? Yes you have stood in the rain before but you have not stood in this rain. One of my new slogans I'm trying to put into practice is, "The map is not the territory". If one has not had many relationships, there's a whole new territory to explore?

My second piece of advice would be to see if you can wait until you get to college or work/out in the world a bit yourself after next year? When you are on your own more, have to learn to rely on yourself and get along with people in your dorm, etc. a whole lot of learning can take place about getting along with other people and there's a whole lot more opportunity to explore things more to our liking and make more personal choices (of what to study), etc.