Cancellation policy is a trap, book through the ai...

Cancellation policy is a trap, book through the airline. Booked a flight with them for Westjet to England then Aer Lingus to Dublin on the last leg. Because Aer Lingus does not provide refunds they are refusing to refund the WestJet portion too (so if i had of booked it through WestJet in the first place i would be getting my money back) Very frustrating.