I could say that will teach you to live in Gosport but that would be going too far.
We have never had a bank card cloned but have had both his personal and works credit card cloned and it was sort out with in days both times. In the case of the personal one we had only used it in two shops and both were a good three months before hand. So how they got the details is anyone's guess.
Pleased you got it sorted out. The only thing I would say is that even if you and your partner have separate accounts with the same bank they may not associate the two accounts and also there is not the same redress with debit cards that there is with credit cards. Which is why I never use a debit card online.