Impairment? Regardless, that doesn't make them inferior people, and neither does you. There are very capable impaired people, don't underestimate what they can do. At the same time, having depression isn't anything light, it drains your life away, and it's very respectable to take a break because of it.
I'm very sorry to say, your parents have failed as such. Having kids implies responsibility. It's a contract one signs in blood the moment the son is conceived, in which one promises to support them, to love them, and to bond with them.
Reading your story, I see two people who don't care. Their neglect is
never your fault. You aren't the nuisance here, because you didn't cause this.
Remember you are a valid person, not the one to blame or neglect others.
We are all with you, we won't let you alone on this. Best of luck tomorrow.