Why do love and family threaten the power that Big Brother has over its citizens?

Love and family are two powerful aspects of human life that threaten the authority of Big Brother and the government's control over the population. In Oceania, the Party's goal is to create a threatening, dangerous environment that turns family members against each other until each member is only loyal to Big Brother.
Love is one of the strongest human emotions and can influence citizens to choose family members, relatives, or significant others over the Party and its agenda. In order to prevent intelligent individuals from falling in love, the Party attempts to undermine the natural human emotion by removing eroticism from the act of sex and forcing couples to spend their leisure time volunteering for Party functions. The only love that the Party encourages is reverence for Big Brother. Similarly, family is a natural human institution, where members and relatives form close bonds that can threaten authority figures. In order to undermine the family unit, the Party members encourage children to spy on their parents, and married couples are required to disclose personal information to Party officials. The Party is aware that love and family are extremely strong aspects of human life that can attract and encourage dissidents to rise against the oppressive government of Oceania.