Big hugs to you NK.
It sounds to me like you need to seek professional help for your alcohol issues before you can start work on anything else.
No doubt you are aware that much of your problems stem from your relationship with your parents. It seems to me that a person could become President of the Universe and still feel worthless if they have had highly critical parents.
There are so many things piling on top of other things here that it must feel difficult to know where to start. Can you change jobs? In my extremely limited experience, it’s very very difficult to change the dynamics in your working environment – sometimes the only option open is to leave. I don’t believe in dead-end jobs and I believe the concept of a ‘career’ is a troubling one, but that’s just my stuff.
It seems to me that you need to deal with this one step at a time. I think it would be better for you to get into another job where the atmosphere is better – even if in your eyes its still a ‘dead-end’ job. I don’t think you can focus on your career until you have begun to deal with the other issues you have. At least this way your work environment would be happier if not ideal and you can then spend your energy focusing more on yourself.
I think perhaps you need to sit and think for a while about what your boundaries are. What will you accept from others and what for you constitutes crossing the line? You need to know what you stand for before you can stand up for it.
I hope you find a solution that suits you.