My parents don't believe me, I'm losing my friends *TW*

I've been struggling with what I think is depression since my early teens (I'm in my late teens now), but it's hard to pinpoint/remember the exact year it started. I've never really understood why because when I look at the cold, hard facts I really have to reason to be depressed at all. My family has never been abusive or anything close, and we've always been well off, so no problem there, and I've never been considered either stupid or ugly. Nonetheless, I've always felt so... empty? if that's even the word. I don't think it is, because I have something there, it's just so dark. Most of my nights I cry myself to sleep over petty things I'm too embarrassed to mention, except for I know it's more than that. I don't really think I can type out the way I feel, it's just a deep pit inside of me. When I get upset, my whole body aches and is consumed with pain. I wish I could be anyone else. I know these feelings are probably natural to the average teenage girl, but I cannot escape them. I fake my smile and laugh every day, lie to all of my "friends", and I'm really good at it.
Everyone knows me as that super optimistic, happy go-lucky, innocent girl, but the real me is such a contrast. I hate myself and my life and situation, and everyday I only pray that my life will end. I've seriously considered suicide in the past, but as of today I am sure I would never actually go through with it, and it's more of always-present background music, but honestly life is just so bleh. I mean, really? I am so finished with all of these bad feelings and failures and disappointments, and just so bored. For the past six months, I've just grown so indifferent to the world around me... I'm going to college so I can make money so I can do what? just keep living in this shell, more unhappy and more bored?
I've tried so hard with the 'positive thinking'. Yeah, yeah, it works on one level, but it never penetrates and just gives me this artificial high on the surface. The higher I get, the further I fall and the harder I crash. But I want it to work! so I keep trying, but I always end up here, because that high part of me is just trying to fool myself into believing I'm happy.
I'm becoming so separated from my friends. Lately, I literally do not care about their friendship at all, I just feel like I should keep my friends because that's what normal people do haha, and I'm normal. But I've cut myself off from myself, I can't even console them when they're sad because I really can't get in touch with my 'feeling' side anymore to create the appropriate words and responses, only my analytical side, which really isn't good at those kinds of things. I have withdrawn myself emotionally from their friendships, thank goodness, so I don't really have to contribute anything but his unrealistic personality I put forward... but I've just become so fake I really don't even think of them as friends, just big dummies.
In addition, my self-hatred has been manifesting itself as self harm. I never wanted anyone to know I was doing it, so I decided I would *mod edit* thinking the scabs would be hidden, but they weren't so I just made up an excuse everyone believed. Whenever this one song came onto the radio, don't even remember it now, I would *mod edit*, but I never meant to. Honestly, though these things hurt me, this fleeting, short pain was not enough. I needed to do something that would internally and externally follow me forever... so I would not turn in schoolwork. It sounds so stupid, but I had always been proud of my grades, and this way I was embarrassing and hurting myself, and forcing others to punish me, and ruining my future. I would even do the work, just never turn it in. Right now I'm extremely behind, and as always I want to fix it, there's just this bit of me that keep stopping my self. the I think part of that may have also been to capture my parent's attention...
My parents. they never understood me or listened or took me seriously, and still don't. Whenever I would get really down on myself, my parents would insisted I was just over dramatic and my mother would yell at me to 'get over myself'. It is extremely hard for me to admit I need help, and when I asked them to take me to see a physcologist (my third time begging, always after a big explosive argument), they would agree but never follow through. My parents think I control depression, they also think one simple thing can make you depressed, when in reality nothing made me depressed.
I find myself just always pretending, living in this little dream world where everything is perfect, and sometimes I just act like I'm in it too, to avoid responsibility.
I still don't feel like I've conveyed how I feel inside, but how can I fix this mess of my life?

There is something wrong, you should see some one about it. Let your parents know you really need to see some one about it. Your parents say get over your self because they think there helping, but, there really not helping. You are self harming and clearly depressed. Look up clinical depression, learn more about it so you can see if it sounds like you, then tell your parents facts.

It sounds like you have a lot of pain bottled up. Just because your life is great on paper does not mean that you don't have the right to feel the way you do. Besides, depression is genetic, from what I hear, and if someone in your family has it (you might not even know, especially if it's not immediate family) then you are more likely to have it as well. It's not your fault, and you definitely have valid feelings and deserve to be cared for and listened to.

Have you considered seeing a therapist? I have found therapy quite helpful.

Always feel free to PM me if I can help. Huge hugs and keep talking.

Your parents probably don't want to accept that anything is wrong because they think that would mean they had been bad parents. You can either try to educate them about depression or just get help on your own without them.