Hey Lexi,
I know what you mean about being immature. I'm 25 and I'm still living with my parents. I've also never really developed close relationships with people.
I did well in high school with the stucture, but now that I'm in university with no one giving me detention if I don't do my homework, I'm failing.
I think I still need people to check my homework. I can't seem to do things like that on my own.
I've never lived on my own. My Mom cooks and does the laundry. My room is messy and sometimes my Mom comes in and cleans it for me.
I think mentally I'm probably about 12 too.