Oah, I completely feel ya! And nobody understands it either!
A friend that I sit next to in one of my classes has bipolar, and she gets it. You wouldn't believe how supporting it is to have someone who has actually been where you are. While our diagnoses are different (I have MDD) we are still able to be there for each other and encourage each other on a bad day.
Depression and other mental health issues are so so common. But people are so so ashamed to talk about it. You would be surprised if you knew how many people are actually going through the same thing as you. Try looking around and reaching out, you never know what good it could lead to
Best of luck to you, my friend!