Even our "national airline" Aer Lingus issues tickets that are nonrefundable regardless of how long before they were booked. (I wonder how many people really read the rules and regulations when booking Aer Lingus on the internet and ticking the box that says they have read those rules)).
Aer Lingus do allow various changes -at high fees , bit cancelling - no refund on what they call "low" price tickets.
Taxes ,however, must be refunded -though some airlines/agents charge a fee even for this.
The one possible escape route on this is for the OP to ask for proof that she was told the fares were nonrefundable - e.g. a signed booking form.
If no such proof is forthcoming then OP can play hardball and say that she not told of the cancellation policy and that she will take this to court/small claims etc. It's almost free to take such a claim ,it takes many months and OP may not win, especially if the agent swears that they tell all clients that the fare is non-refundable.
I'm not aware of any insurance that would cover this.