Well congratulations on a judgement, and watching her show herself up in an actual court must have been worth a fair bit of the debt.
I see decisions like this (the ones that make you go wtf? no sensible person would decide that) sometimes at work, and I think they do try to think through the logic as far as they can, but basically a lot of them are legal decisions rather than common sense decision that most of us would arrive at.
I think in this case she was awarded the benefit of the doubt over this email she supposedly sent. Personally, if I was the judge I would have disregarded any references to the email purporting to state the debt at that timepoint, unless it could be proven that she did send it when she said she did (unlikely I suspect).
That said, £3.5k is not to be sniffed at and it is better than what you had before, i.e. zero. Well done for seeing it through, but I'll reserve the champers fuelled celebrations until the cheque has cleared
Has the facebook post telling all about her shit day been made yet?