What you describe is honestly so close to my own life, it's kind of eerie. I had emotional neglect growing up, and still now as I still live with that parent. I never learned properly how to identify my own emotions, and the only emotion I could really identify in someone else was anger or disappointment. I also had a time where I thought I may be a sociopath, for the same reason as you. I had learned, very early, that dissociating from it all was much more comfortable than believing my own parent could be like that.

I developed c-PTSD and DID (multiple personalities) because of this, which is hard to explain to people (meaning professionals), because their response is usually along the lines of "being distant and emotionally unavailable isn't abuse." When you are a toddler, it sure a hell can feel like abuse, and my toddler brain reacted like an abused child.

Years into therapy, I still have a really difficult time with emotions. The only thing that has helped me are these sheets of paper that I would ask for in group IOP, that have the faces on them. Under each face is the name of the emotion it is showing. I learned to identify how I was feeling with these. Other than that, I was either good or bad. I'd get frustrated when a T would ask for something more descriptive. I didn't know.

Even now, without being able to look at one of those papers (you can also find some images of them on Google, keyword emotion faces sheet, or something similar), I am still limited to happy, sad, afraid, and angry. The main thing is that I have learned, over the years, words for different levels of these. For example, glum and depressed are both sadness, just different severity, and frustration and rage are levels of anger. I started using a scale system with my pdoc on certain things. Zero to ten. Zero is none and ten is worst possible. Anxiety (fear) and depression/suicidal thoughts are the first things we started using it for, and it's helped to give him an idea of where I am without having to identify anything more than fear or sadness.

Hope this helps in some way.