Just scan in or make a photcopy of the card you used to buy the ticket.

A photcopy or scan of the photo page of your passport should keep them happy, in the absence of another form of 'photo ID'.

All this has to do with money-laundering/fraud/anti-terrorist regulations etc. It's no big deal. Nobody is trying to steal your ID. Just go along with their little rules.

Upload them into your PC and send them off to your lady. She prints them out. Job done.