Motor mount broke

i have the car listed above that is front wheel drive and a 5-speed. my motor mount on the front left broke (the one for torque). or it was about to fall apart because the rubber had worn down . my mom is trying to kick me out because she thinks i am lying because the mechanic told her that it was from spinning the tires and holding up the e brake and burning them and i haven't been doing any of that. so i was wondering what might be some other reasons that this could have broken since she wont believe me. any help would be greatly appreciated. thanks for your time!