Thanks all so much for your responses. So many of you are saying what I know already, that I am the parent and I need to take the decision. But it's very difficult to hold on to this when someone is doing their best, and often succeeding, in making you feel guilty and afraid.
Re the bursary, I've made enquiries at Oswestry school and they don't have any funds left for next year. Adcote have advised me to apply and see what happens and have asked me and DD to visit. So yes, it's not a guaranteed thing but all I can do is encourage DD to visit the school and show that I want her to be somewhere she will thrive and that if she refuses to visit, that is up to her if she wants to settle for a school that may not suit her so well.
DP and I have been together for a little over a year. I visit him in Wolverhampton. I didn't want him to come to mine as I worried the stressful atmosphere between me and my mum would send him running for the hills asap, although he is aware of the situation. I don't know yet if we will end up living together but we both would like to be nearer each other. Once I'm not living with my mum and if we're nearer each other, he can spend time at mine and also get to know DD and I won't have to go to his and be away from her every time we meet up.
Re the counselling, I already asked our GP for referral for DD earlier this year but when it came to arranging appointments, DD flat out refused to go and is still refusing to go. Difficult to force anyone, child or adult, to engage with counselling if they don't want to.
For last 6 years, mum has been living with us in my house (although she helped with the deposit and I owe her her share back when I sell. I've paid all bills and mortgage). Before this, me and DD lived with mum in her small house and I paid her mortgage and bills (living there was meant to be temporary for 6-12 months after DD born until I found my own place, then mum acted up every time I tried to leave, including when we moved and I bought my own place, unfortunately I was weak amd alowed myself to be guilted into letting her move in with us, thinking that in a big house she'd respect my space and let me get on with my own life. Wrong).
The actual practicality of making DD do what she does not want to do is extremely difficult as she is as tall as me and physically stockier. I am a slight 5ft1 and have postural tachycardia and also currently a slipped lumbosacral disc. When I ask her to do something she doesn't want, especially if it's something big that she's angry and upset about like the move, she can get physical, will literally refuse to budge and can kick and shove. I am not physically strong enough to pick her up and put her in the car. With my mum around while this is going on, the situation can get very charged and is to be quite honest a nightmare. I am currently thinking I will have to compromise and stick with buying a house in Hereford where we currently live and keep DD at her current school. In that situation my mum would be living about 5 miles away. I have clearly expressed to her why I am desperately unhappy with the current situation.