I can understand about parents not being able to understand you or want to.
I was only able to visit my mother (maybe) two weekends a month if I was "good" from the age of three. Then when I was 12 I got sent to group homes and foster homes until I was 18. My mom visited me once and I would go to her house for Christmas and Thanksgiving...that's it.
My father never bothered to get to know me and we don't talk now. My mother just passed and I was able to get to know her just a bit and she got to know me a little.
Gosh, I feel you! It is so hard. You can't make someone want to get to know you. It does NOT make you a bad person, someone who doesn't deserve it or less of a person. You DO deserve to feel wanted.
I suspect your mom doesn't know HOW to get to know you. She may, also, be afraid that you will be taken away again or that you will leave, so she stays on guard, so to speak. I am not in her mind, but I am thinking about how I would react if it were my daughter.
I hope you are able to feel the love and caring you so deserve!
BJ