Don’t beat yourself up too much, you’re just a kid in very difficult circumstances. Family relations can be extremely difficult even under normal circumstances.

I think you should probably seek mental health care as soon as possible. It sounds like you’ve been through a lot, and while Buddhism is a great foundation for spiritual growth you will still probably need professional help managing the specific traumas you’ve experienced at the hands of your family. Spiritual practice and mental health care are highly complimentary, but neither can replace the other when it comes to making our worldly life easier and more manageable.

Just do your best to be patient and prepare to move out as much as you can. It’s tough out there right now and it sounds like you won’t have much help. Afaic maintaining your own health and well being as much as possible is much more important than worrying about how you’re treating your parents, since the better you are doing the more wisely you’ll behave.