I don't understand

Why people want to be alone when they're sad. It just doesn't make sense to me. When they're going through something and they just don't want to have anyone help them. Whenever something bad happens to me, I always want a hug at least. I always want to be around someone who I know will make me feel better. Like this morning on the bus on the way from the high school where I take choir to the smaller high school where I spend the rest of the day... I started crying because I realized I still like someone, not because he told me he wanted to be alone. Yesterday I sent him an email saying that I didn't like him anymore well, I mentioned it in the email. Because I thought he wasn't replying to emails and texts or answering my calls or calling me back because he doesn't like me anymore or something. I don't know. Weird girl stuff. Anyway, I told him that I didn't like it and I meant it 100% last night. I've spent weeks trying to get over this crush because we both have lives and we need to move forward. Having a crush on someone for this long only weighs me down. But I realized that I do still like him. I feel confident putting this on my blog because I know he doesn't read it. And I'm not saying his name.
Anyway, I'm at lunch at school now and I'm just feeling really weighed down today. I'm not sad or anything, it just feels like I'm dragging myself from class to class. I definitely failed my algebra 2 test today and I'm kinda mad at myself for that because I've been working so hard to keep that grade up and going. I just want to go home and drown my thoughts by studying SAT stuff and doing personal progress. I always feel so much better when I do those two things.
On saturday I have the PSAT. I hope I do really well on it because it will help me be a little more prepared for the SAT, which I take in december. My mom bought me a HUGE SAT study book from Princeton Review. It's amazingly terrifying to see just how enormous this thing really is. It's bigger than my algebra 2 textbook. I have only 2 ish months until the test and I'm going to be studying like crazy. In my spare time I'm going to practice "couldn't hear nobody pray" to my keyboard's metronome so that I finally get it 100% right next wednesday when I meet with my mentor again. It's hard learning how to keep a constant beat because its a lot easier on cello because you just hold out the note with your bow until the conductor moves on. Cello is kind of one of those instruments where when you're reading the music, as long as you get the notes right and look up and follow the conductor, you're pretty much golden. I miss playing the cello. My senior project is difficult and yesterday after school, I spent about 40 ish minutes with an internet metronome going at a constant beat trying to get the first few lines of couldn't hear nobody pray absolutely perfectly.
Well, class is starting up again. I'll try to make the rest of the day a better one. Hope yours is better than mine :)