The Party uses a variety of methods to prevent people from forming loving relationships. First of all, the Party controls the institution of marriage. If two people wish to marry, they must be approved by a specially-appointed committee. If the two people appear to be physically attracted to one another, however, the Party usually refuses its consent.
Secondly, the Party has formed organizations like the Junior Anti-Sex League to promote the ideal of celibacy and abstinence. By doing this, the Party ensures that children grow up without any interest in forming a loving relationship with another person.
Thirdly, the Party uses the telescreen to monitor the movements and conversations of its members. By watching people constantly, the telescreen acts as a deterrent against breaking the Party's rules on "forming loyalties" with other people.
Finally, alongside the telescreen, the Party uses the Thought Police to make sure that nobody disregards its rules on relationships. Individuals know that if they break these rules, they will go to Ministry of Love where they will be tortured and interrogated.
Among married people with children, we must also remember the children's Spy League. They are taught, much like the Hitler Youth, to report anything their parents do or say which is against the Party. Therefore, with the help of the telescreen, people are never safe to allow their true feelings to show.
The party destroys loving relationships in many ways.
It preaches hate, making love harder to sustain.
It makes sex unappealing.
It encourages people to value Big Brother and the state over one another.
It spies on people.
It sponsors anti-sex leagues.
It creates a language that will eventually define love out of existence.