I think im going insane?

I have a cut under my eye and now its black and puffy...why? my older sister who is 21 and has three kids was looking at corsets last night...I simply said said why don't you were clothes that are more appropriate It makes our family look bad (her wearing sleezy clothes).She then started saying i was jealous and that im fat and no one likes me...we got into to pretty bad.So i dropped it and went to bed.Well earlier i was making dinner and she started it back up again I kept telling her to quit but she wouldn't I snapped and went and puched her in the face and we started fighting.Her huband who is a peice of **** broke it up and said since we called the cops on him for beating her that I should have them called on me...I told him to go screw himself.I cant handle being here anymore...am I going insane?