Hmm, she sounds like the way I was when I was her age. I know that stress can really affect a child's self-esteem.
I think the most important thing you can do for her is to maintain a stable, loving environment where she feels safe. Therefore, if anything does come up, she'll know where she can turn for comfort.
When I was in school, I received special services to help with my organization and my social skills. I understand that she is homeschooled, and I don't know how these services can apply to a situation like hers. Maybe you could get her a tutor to help with organization, and/or a social skills coach on appropriate conduct. Such services really helped me. It sounds like you are carrying a large amount of stress, and it may help to get an outsider's perspective on what she is capable of.
Raising a child seems like so much stress - the entire well-being of a person is a lot to think about. Try to take things one day at a time, and regardless of how she is in the long run, it is important that she is loved. It sounds like you are doing a good job. Love her unconditionally, and take a chance to relax whenever possible.
If you have any questions about my experiences, feel free to PM me. I'm no expert, but I can relate to where your daughter is coming from, and was raised with my parents fighting to get me services in public schools, so I know a lot about the stress aspect as well. Believe me though, you're not alone.
Let me know if you need someone to talk to!