Besides knowing the differences between cities and general feel for each of the campuses, this is impossible to answer because each class is different. There could be no families in the next incoming class (unlikely, but possible). I know in the class of 2016 there are more married couples and families than usual, but I don't think anyone feels left out, or like they're lacking study buddies. There's a camaraderie that happens in med school, or at least with our class at CHM. You're all kind of "in it" together, and friendships are made quickly- partially to help each other study, but also to commiserate. Friends and family may not understand this part of your life, but your med school friends certainly will. So, pick a campus based on where you want to live for two years and don't worry about too many married couples, or not enough, or whatever because you can't predict the demographics of every class.
Their GR campus, especially, seems great.
