This girl posted on FB daily until around late February. I saw that rude poster you mentioned and wondered what connection she had to this girl- she was her mother's age, and yet she's calling the poor girl ugly.
Looks like there's some issues in her family, although, nothing that I could see that would have me thinking one of them hurt her.
However, I do suspect foul play. I live in NH, too, an hour away. Keeping my eyes and ears peeled. This is the first I have heard of her being missing, and it was her roommate that said the last time she saw her was in June OR July- her roommate can't remember when she last saw her? It was just recently, according to her!