I understand that it isn't about 'not being bothered', I hope your DH can understand it is a lot more complex than that. I think modelling good eating habits for your DD is a really good thing to aim for, but also even more importantly, modelling self worth. I know you can't just 'do' that, but that needs to be the goal too and will be key for both of you by the sounds of it. If you think about how much you value her, you want her to value herself that much too. You can only really teach her that by valuing yourself as you should.
That means that you decide you deserve to be healthy and feel good, that you deserve to succeed with weight loss. But you also decide that your intrinsic value is just as much now, before the weight loss begins, or without weight loss. If you think about DD, why do you want her to be a healthy weight? Presumably because you love and value her, and so want her to be happy and healthy. Not because she needs to lose the weight to be valued. Try to apply the same to yourself.
Your self worth needs to come first really. There might be some good self help books out there, but I also really think a counselling referral is a good idea. If you can afford any privately while on the waiting list then it would be worth a try till the NHS comes around, but if not online resources and self help books will help to tide you over.
You could also ask your GP about ADs - I know that some people find they cause weight gain but that can be counteracted if they help with mood and impulse control.
www.nhs.uk/Livewell/loseweight/Pages/WhataGPcando.aspx
Your GP might be able to refer to other doctors/dept that manage weight loss. There might be some good advice on the weight loss boards here.