why my sister is like this?

My sister had it out for me since we were little. She hates everything I do she hates what makes me happy she hates my children and husband..she called my children lowlifes she called them animals she called my whole family animals she almost cause my other son not to see me that I had with my ex. She called my son an animal. Everytime I'm happy she try to put me down. Anything like any casual clothes I wear she don't like. She called me a deadbeat mom cause I didn't want to be with my x nomore for domestic abuse was horrific and plus he took of with my son she call me deadbeat mom cause of that..she don't accept no my friends or my husband who makes me happy...she hates everything about me with a passion and those that associate with me she hate with a passion. I didn't do nothing wrong to my sister to act like this with me. If anything I saved her from getting jump on by a lot of so called friends of hers I always kept putting a stop to it so she won't die from them beating her