1. If you didn't talk to her that much, don't try to reconcile things by now trying to be her facebook friend. It's not going to help anything. Not to mention that is not respectful at all.
2. Don't call friends close to her to "find out what happened". That's just fucking ridiculous.
3. Don't talk about what just happened; trying to find out details. If you don't know, you're not meant to know.
4. Stop spreading rumors. It's none of anyone's business--including everyone at Swampscott High School. Grow up and respect people's privacy and right to mourn.
5. Don't believe everything you hear.
Is it really that hard to mind your own business and let all of her friends deal with the tragedy? I can assure you, random people trying to talk to her is in no way, shape or form going to help anything. So please, just let it go.