What should I do? (Tw: abuse, neglect)

I've lived with my grandparents since I was six years old. My mother is mentally ill and unable to take care of me. My father used to be incapable of caring for me because he was in the military until I was eight and he suffered from ptsd.

I don't remember too much of my early childhood (for one because it was my early childhood) and also because of the trauma I endured. What I do remember is not fun. I had to feed myself as a child which was mostly flat cheese and cold hot dogs from the fridge. When my mother was able to feed me (she has bipolar disorder and when she's depressed she didn't get out of bed; when she's manic she also gets OCD and she can't help herself-- she spends all of her money on makeup or whatever else) it was usually fish sticks or chicken nuggets.

Sometimes she would lock me in my room for days so that she wouldn't have to bother with me.

I remember when I was starting to get ready to leave I didn't really understand what was going on but I knew that my grandparents (paternal) were at my house a lot. I don't really remember much of that time though.

Anyways, recently I remembered an instance during that time where I only had a few pairs of underwear. I refused to change my underwear and insisted on wearing the pair I was wearing then. I mentioned this to my grandma and told her I don't remember why I wouldn't want to change my underwear.

(Warning: this is the part where it begins to get... well this is why it's under this topic)

She told me that it's good that I don't remember that. This makes me think that I wouldn't want to change my underwear because of sexual abuse. I also remember when I was younger and after I went to live with my grandparents that I would hold myself a lot and not like to go to the bathroom. I don't know if it's related, but I also don't have a hymen. I might have been born without one though (hopefully).

I didn't understand much of what was happening nor do remember because I was so young. I don't know if i want to remember. My trauma has followed me my whole life sometimes it's just so hard to deal with.

Sorry for making this so long rip. Thanks for listening (reading? Whatever, you get the gist).