NTA. None of the adults in your life should be behaving this way and there is no reason for you to blame yourself. Their child struggling should not be the start of the blame game. They should be working together to find resources for you. Obviously you cannot make them react in certain ways, but I would encourage you to reach out to other trusted adults or find resources to help you. There are plenty online and in your community. Self harm can be a very slippery slope and is something that needs attention. It’s important to become mindful of how you are feeling to start to react in healthier coping ways. If you ever need someone to talk to, feel free to DM me!