Families in general have ideas about who each person should marry, and they are often very vocal about the subject. They want someone who will enhance the life of their loved one, and this person must also be able to interact well with the whole family. The goals of this person must fit into the goals of the family, or they will be rejected by the family. If a single person is suddenly the only unattached one left, they may find the family would rather choose their significant other than let them find someone on their own.
Families do care about their members, but match making often appears to tell a different tale. The potential mate that pleases the family is often perceived as flawed by the person they are matched with, and this makes the single person wary of how much the family cares.