Sorry you are going through this, but glad you have come here. You will find much support here
Knowledge is your power. You can make any decision you have to once you know what your legal rights are. As it is your parent's house it does seem like it will be necessary for you to let them know what's going on. I'm sure that's not an easy task. I know that I tried to make my xabf look like he wasn't so bad to my family, but all they had to do was be around him to know that he was a little off the wall and over the top.
Good luck. Keep posting here and asking questions. We will be happy to support you.