I'm not one for labeling people. I'd much rather focus on the unhealthy behavior, figure out why it's continuing, and work to end it. Any adult child who's still allowing themselves to be parentified when they're aware that it's happening, must ask: “What's in it for me? How am I benefiting from this? Do I really want it to end?”
When faced with these tough questions, a person may feel defensive at first. Their immediate reaction may be: Of course, I want it to stop. I hate being parentified. I want my parent to nurture, guide, and support me, not the other way around.
However, as someone who was parentified for years, I now know that I allowed it to go on long after realizing how unhealthy it was. I let it continue as a teen because I was flattered that my mother, a grownup, was seeking advice from me, a kid. It made me feel important, needed, and mature.
As a young adult, I let it continue because it was all I ever knew. It felt familiar and safe. I also understood that my mother had created this parentified relationship between us because she wanted it. I knew deep-down that if I ended it, our relationship would be over to a huge extent. At that time in my life, I didn't want to risk losing that bond.
The parentification can only continue if you permit it. If you choose to stop it, your mom will probably distance herself from you. She'll probably find someone else to use as her therapist. You must be prepared for these outcomes.