How can a young man's desire to choose his wife himself be reconciled with his family's desire to marry him to a woman he does not wish for?

Scholars have stipulated that it is not permissible for parents to force their child to marry someone he does not desire. Therefore, you are not obligated to obey your mother in marrying this girl. However, if she is a woman of religious commitment and good character, and you marry her out of devotion to your mother, then that is good. But if your mother prevents you from marrying a specific woman, the default is to prioritize obeying her, unless you fear falling into temptation yourself.