Was this issued in the USA? If so, then you should be able to cancel the reservation and use the ticket's value - minus the change fee - towards a subsequent booking, though I guess it depends on the precise conditions in your booking. It is effectively a credit note. If it was issued somewhere else, different rules may well apply. Be a Gold cardholder won't make any difference here.

Incidentally, if what you are seeing relates to the online screen: if you had already changed the ticket, or are very close to departure, you are out of the "self serve" mode. Ditto for other complications such as using an e-voucher, part payment via Avios and other oddities. So the refund process doesn't give the specific amount available to self serve bookings, instead the refund is calculated manually. This may explain the difference from your wife's booking. If it was the same fare basis then the same result should happen for your booking too, but I suspect it wasn't. You need to call up to get better guidance rather than relying on the online process.