Daisiemoo "Im not parenting on my own, however DH is working way more than he should so parenting gets left to me." So you are parenting alone some of the time. When you say he is working away mire than he should do you mean you don't need the money or he doesn't need to do the work?
Can you talk to him about how to share the load more?
"The main thing that causes all of this is homework! "
Stop the homework immediately. It is not worth it. It has very little impact on education at primary.
Just stop trying to get her to do it. Talk to school. If she is 10 or 11 you may find a school time club that tackles homework and she might benefit from it. But prior to Year 6 I would avoid homework like the plague.
Is she dyslexic? My dd is, and on the spectrum. She is now 13 (birth child) and we stopped all homework in Years 4 and 5 I think.
"DD is behind at school, and just doesnt want to do it!" I don't blame her I hated school. I think you need to focus on fun at home and maybe school will work itself out more.
Totally agree with Ted27 "I just want my son to do the best he can do, if its 'behind ' the other kids, I don't really care to be honest - they haven't got to deal with what he has to"