Kulula cancelling return flight without notification

I booked return tickets with Kulula from Jhb. I missed the flight to Durban on Thursday and so booked a new one-way ticket on Friday (as I intended to use the original return ticket on Sunday). On arriving at the airport to fly home with my gf i was told my flight home had been cancelled because I missed my first flight.. This, despite the fact that I booked the replacement flight with Kulula! The real kick is that I wasn't notified... not a single SMS or email or any contact in any way to ask if the ticket can be cancelled or even that it was going to be cancelled. On questioning this at the help desk while standing at the airport I was simply told "It's in the terms and conditions". I understand this to be ******* and I would like my money back. I paid for the seat and I expect something in turn for my money!