There are plenty of theories why someone would want to control you. One is that people who can’t control themselves turn to controlling others. This happens on an emotional level. A person full of insecurities has to exact a positive sense of self from other people because their self esteem is too low to do it for themselves.
Maybe people control because they are afraid of being abandoned. They don’t feel secure in their relationships and are often testing to see if they’re about to be betrayed. The paradox is that their behavior creates exactly what they fear the most.