You're describing what my mother was like when I was a child. She drank that way for a long, long time. I never saw her drunk as a child, she just drank all day. She may as well have had an IV drip to help her get through the day.
When she tried to quit, she found she could not do it. As a child, I found myself constantly worried about her. I took care of the house as best I could so that she wouldn't have to come home and be stressed out and drink. She drank anyway. I figured it was my fault, I hadn't done a good enough job taking care of the house and making sure everything was perfect and stress free for her. I felt an overwhelming sense of responsibility for her .... so much that I lost myself in the process.
She ended up loosing her marriage, her job, her home, a good relationship with her children, and nearly her life.
I'm happy to say that she is now sober but she didn't get there until she ended up in assisted living in her 50's. She has improved now but she drank herself nearly to death, to the point that she could not feed herself, or bathe herself, or walk ... among other things.
I never saw her drunk until after she announced that she had a problem. I remember when she announced it, I was in my 20s .... I thought, "Wow, really? I knew that when I was 11."