Did you start homeschooling right away? If so, she needs a break between school and homeschooling to get used to being home, get the "school" aspect out of her system. Especially since school was a bad experience (bullying, etc.), she needs a break.....sometimes longer than a month.
I pulled my 11 yr. old son out of PS in February and gave him about 5 weeks off. I was going to go longer....but he seemed like he was starting to lazy (not a nice way to put it...but laying around a little too much) so I started HS. I started out slowly, about what I thought would be a part-tiime rate. So far, it has gone OK. He gives me grief, etc., but also has some really good days too.
Maybe she just needs a break??
Good luck:)