violent child

My teenage daughter Abigail has Aspergers Syndrome. Up until a year or two ago she has always been a very calm and quiet girl but now she’s got very angry and she has meltdowns and outbursts frequently. She’s never liked school that much but always went but now she’s got to go back next week and she’s in a terrible mood. She’s cried and screamed and she hit the wall which hurt her hand but she won’t let me look at it. She’s also got a problem with herself. The other day she hit her face and made her nose bleed. When I asked her why she did that she said because she’s a monster. All this began last year after my husband passed away. I have a younger daughter who is seven and she is also quiet but never aggressive, she seemed to have coped with the loss of their father a lot better than Abigail has.

I also have Aspergers but have never been aggressive so I really don’t know what to do to help Abigail. I’m worried about her safety though as she’s started hurting herself and this morning she had a meltdown and threw the cutlery, a fork hit my hand and caused it to bleed. I’m worried in case she lashes out again more worse next time or if she hurts her sister.

Please help if you can.