In reply to Tom Ripley Mountain Guide:
Basically, yes it's legal, each fare has set t+c's with regards to changes/refunds, and you took the risk by accepting one with those particular rules as everyone who books a ticket does who doesn't want to pay the much higher fares for ones they can change more easily.
the only circumstances you may get a refund from (and no you can't blag these, you need proof) are -
+ using a term in your travel insurance such as relating to illness or bereavement if it applies and they can provide adequate documentation.
+ similar terms within the fare which are most likely to be simply be an allowance for if an immediate family member has died.
+ if you weren't advised of the penalties for changing the flights at the time of booking and can prove it. If you booked online don't even bother checking, you'll have ticked saying you've read them. If you booked on the phone you may have a slim chance that you weren't told but best be sure because the calls will have been recorded and there'll most likely be notes put in the booking (not viewable to you) saying that they were read out and/or remarks entered which are on your confirmation which you will have been advised to read.