I worry about her interpersonal skills. How can I encourage her to make real friends and do social activities -- not related to school, church, 4H or scouts (some of which she participates in only because we have told her she has to for a certain time frame). I feel like she may have a very lonely future.
You do not describe her as being shy but as being disinterested or bored with the "normal" activities of kids her age. Does she enjoy the company of adults more than her peers? She doesn't have psychological or social problems merely because her preferences for activities might be different or more sophisticated from those of her peers. Being bored with what other kids do for play is very different than being anxious or frightened to interact with other children.
You night consider trying to find organizations and/or activities that more specifically match up with her most passionate interests, talents, and curiosities. She is most likely to find kindred spirits among groups of children who share similar interests. You might wish to consult with a therapist who sees kids you daughter's age to discuss her asocial behavior. I think you would benefit from a chance to fully discuss your daughter and to perhaps brainstorm with such a therapist about how to encourage a more active social life for her.