Boyfriend makes me look bad

Everytime me & my boyfriend fight .. he tells his mom. That however isn’t the only issue here, he only tells his side of the story and not mine. Makes me look bad and blames the entire issue on me even if it was him that caused the argument. I’m at the point where idk what to do. His mom is starting to have something against me all because he fills her head up with things that aren’t true. What should I do ladies? This has been happening since we got together. It’s been 3 years.