I am sorry, it is foolish beyond belief to consider yourself a failure just because you got ABB instead of what?
One of the key skills you need to develop when you move from the protection of home and school to the big wide world of further education and work, is a sense of proportion, followed by learning to be flexible. Throughout her life, again and again this girl will find things do not turn out the way she hoped and she will have to learn to adjust and chop and change.
There are hundreds of courses in a wide variety of subjects in Russell Group universities that will be only too happy to accept someone with ABB, but she must be flexible. Perhaps Maths is clearly over subscribed at York, but may well not be in other top universities. Alternatively she could do maths and something else or something else and maths. or she could just think of another subject that interests her, not perhaps ecology but there are such a huge range of to choose from.
She needs to snap out of her grief ASAP and get looking, numbers applying to university are down this year. Get out there show that she can cope with the realities of life
There are lots of universities and courses waiting to snap up students with qualifications like hers.