Good question. My best friend moved away over 10 years ago. That was really hard. We were together almost everyday or talked on the phone. We raised four boys together (2 each). I would not say she is gifted academically but socially. She has a great sense of humor and a great imagination and an openess that makes her a lot of fun to be around. I still talk to her often but it isn't the same.
I do not have any close friends now where I live. I was in a relationship that was pretty isolating for a long time. I am also not much interested in casual acquaintances and would rather be alone than make small talk.
My little sister is the only person I can think of right now that is a gifted friend and when we get together it is like returning to my home planet. Unfortunately we don't see each other often due to kids, distance etc.
I realized in contemplating this question that I change the way I talk and what ideas I put forth to accommodate those around me. When I do need to switch gears for a job interview or to speak on behalf of my DCs then I often feel that I am losing my conversational skills.