I see we're talking about Sara's past and how it is so intriguing, yet we hear little about it. I'll put in my two cents.
The last time we really heard anything about Sara's past was in Committed, it was about her Mother and her links to mental hospitals. When Grissom asks her if she wants him to find someone else to be put on the case. Sara says no, she
wants to be on the case. You can see that she has grown a lot, because, especially with what happened in Committed, most people would want to take a vacation after something like being attacked and being flooded with bad memories. Sara is bothered by being in the mental hospital, you can see that, which shows she is still broken.
Through the next two years, [seasons 6 and 7], we hear nothing about her past. Now, when did Grissom and Sara get together? They were living together, or close to it, in Way To Go, so they've probably been together for a long time before that. They could have been living together for a long time before Way To Go too. It would be easier if we knew more details, but anyway. Man, it bugs me; how much we don't know.
Basically, Sara could possibly be completely healed. If so, then it isn't likely we'll hear about her background. Actually, small thought, if she dies and they were to show a funeral scene, I can see some of the CSI's talking to some of her family. Brother, Mother, maybe bury her beside her Father? Now I just imagined a grave with Sara Sidle on it. Now I'm about to cry.
Of course, she wanted to be cremated, but I'm not sure how that works.
Also, Grissom and Sara have probably talked about her past, and he's probably helped her heal as well. Actually, I'm sure he's helped her. He showed he cared in Living Doll. Yes, she does have a past, but maybe she's just worked through it. Her personality has changed since season 5, it's possible that she has too.
Now I'm going to go cry as I try not to visualize Sara's grave, but that only means it's going to bug me more.