Hi LR, hope the mrs is recovering well.
As you say, the choice to give, or not to give antibiotics, is usually made on the basis of probability. (It's not an ideal situation).
Even NICE recognise the uncertainty
http://www.nice.org.uk/nicemedia/pdf/CG69QRG.pdf and allow us some licence to use our clinical acumen (guess).
On the facts you supplied, it does seem a tad mean on the Mrs, although in all honesty, it's likely that her symptoms are viral, so antibiotics wouldn't affect the outcome, and may even delay things further.