Just my 2 cents here. Your daughter sounds like me in 3rd grade. Because of my own less than ideal experiences, I take an active role in making sure we have a family social circle that includes some of DS8 and DS6's friends from school. We are lucky to be in a TAG magnet that is also close to our home, so a lot of our neighbors are also at school.
I tell DS when he says something that might be hurtful or offensive to a friend.
We try to keep his social opportunities broad-based, ie, we still socialize with families from our old neighborhood, we have church friends, school friends, cub-scout friends and friends from our life before kids. Many of these groups do not cross over, although some do.
Neither of our DSs seem to have a lot of very close relationships, but there are varied social situations in which they feel safe and comfortable.
It is my hope that this environment that we are creating will give both DS the social confidence they need for college and beyond, even if they end up sharing our fate (and I think they will) of having difficulty forming close friendships.
Your daughter may or may not have an easier time as she gets older, but I think the broader you can keep her "safe" social groups outside of school, the better.
