Thank you for writing. There is a core of strength in you that hasn’t been defeated despite neglect and addictive behaviors. Please pay attention to your instincts. You do need help. You already know that. It’s sad when parents can’t be counted on to provide the love, support and advice a kid needs. But some people just don’t get the parents they deserve. In that case, it’s important to look to other adults who can be of help.
Instead of drowning or dulling your pain, it’s long past time for you to do exactly that. If there is an adult relative you can talk to, then do. Do not make the mistake of “protecting” your parents’ reputation with the relatives at the expense of your own life.
I do happen to be familiar with the city you are from and know that it has an excellent school system. I’m guessing that there is a guidance counselor or nurse you can turn to if there are not relatives you trust. You need to be evaluated by a qualified mental health counselor and you need to learn what options for treatment and support are available to you. Your school professionals should be able to access that.
In the meantime: It might be helpful for you to take a look at this article: https://psychcentral.com/lib/recovering-from-childhood-neglect/0001384
Please don’t neglect yourself as you have already been neglected. Do break the silence and get the help you need and deserve.
I wish you well.