I should be the happiest person ever. I am a straight A student without ever trying. I'm in college with gigantic scholarships. I have a wonderful, committed boyfriend, and the relationship is only going to be long distance this semester- and that's only a 7 hour drive. Some people have worse. I've made more friends up here than I did last year. So why do I though through phases of being so lonely even when I was just having fun with friends. I can't keep my mind off bad things and honestly when it gets bad I'm afraid I'm going to hurt myself. Once I'm back to "normal" I can look back and wonder what my problem was, but during those moments I'm afraid one of these times I won't be able to keep control over myself. I want so badly to talk to my friends or someone because it would be nice not to keep it inside, but I'm not going to burden anyone with me. My best friend had a hard enough time handling when her sister cut herself, so I know it would be too much for her to know that I'm losing my mind as well. I'll go through times when I'm perfectly fine, but I don't know what keeps coming over me. I had thought it was monthly mood swings or even my birth control pill, but who am I kidding... This has been going on for years before I took the pill, and it doesn't follow any sort of schedule. It just takes one small thing to make me just slightly upset, then I fall apart.

But it could be hormones, and it could be the pill exaggerating the hormones (I can never spell exacerabate). I'd go off the pill and sex for many months.
It could also be that feeling that what you are doing with your life isn't what was meant. By that I mean expectations you had, your family had, and what they did when they were your age. Do they feel right? What about career, marriage, children, all that? Do you have a field of study that drives you, or is it just college for college's sake?
And what about your feelings about your boyfriend? Do you miss him, or worry that you don't? Worry that he is drifting away? Or is this all bigger than a boyfriend (I think it is.)
I was the same as you, maybe, based on what you say in this short space. My mother expected me to follow the college and life path she did, and yet she was miserable with her own life, and it took me 30+ years to figure that out. I dropped out of 3 different colleges and won't go into the rest...

I felt this way for a long time and on the odd occasion I still feel like this. Birth control pills can mess with your hormones a lot. I went and spoke with my doctor about the feelings I was having and the first thing he told me was to go off the birth control pill for a while and see if that improved my emotions, I then got changed to a different pill.

I know you don't want to burden your friends with you "problems" but please rethink that as you may be surprised at what you could learn from them, even find someone older that you trust to talk to, talking about your feelings is usually the best way to understand them. Maybe you could try keeping a journal so you can look back at your feelings and see if there is any sort of pattern with your down days.

A lot of rambling but I hope some of that may help you. Keep us posted :-) and keep safe and try to smile.

Dude, I've felt this way before, you're not the only one with this kind of problem, trust me, I've felt the same. I sometimes look back at all the possibilities of my problem, and when I find it, I try to find a way to fix it. Sure, it can be pretty scary, because like you said, you don't want to upset your loved ones. But either way, you should try talking to your parents or other family members, I'm sure that they would help you because they love you. But if you keep these emotions bottled up inside, no one will be able to help if they don't know what's wrong with you. Don't be scared to tell a friend your problems, you may just realize how important it is to have them with you, and that they can help you and support you no matter what. Don't worry, you'll find a way out :) I know I have, millions of times.

Maybe it could be a medical condition. I would suggest talking to trusted family doctor or someone with medical background. Stay strong, and it's OK to open up. Just make sure you're being safe and smart.