Very disappointed at the level of service received

My husband and I were booked on the 08h30 flight to Cape Town on the 20th of October from Lanseria airport, returning the 22nd of October. We left home at 06h45 and should have reached Lanseria airport by latest 07h20. However, there was a huge accident on the N14. When we approached the accident, there was no where to turn around to maybe take another route to the airport. The terms and conditions of the ticket states "If you fail to check in for your flight on time, this will constitute a cancellation and you may forfeit your ticket without refund for your entire journey. If you're running late, call us ahead of time, we'll try to change your flight so you don't lose out." Being stuck in traffic, I didn't call to try to arrange another flight as my aim was to get to the airport as quickly as possible. We reached the check-in counter by 08h00, out of breath from running, the lady who assisted us, told us sorry, the check-in has closed. We tried to explain to her that there was an accident on the N14 and she told us to go to the Kulula ticket counter to get a new flight. With the 20th being our 10 year wedding anniversary, I had made a booking for us in Clifton for the night. Terrible start to a day that should have been uncomplicated. The lady at the Kulula ticket office told us she could only get us on a flight at 19h30 that night. We left the airport and returned home to go and see if we can maybe catch an earlier flight on another airline. We managed to find a flight down to Cape Town at 15h10, resulting in us having to buy 2 additional one-way tickets to Cape Town. On Sunday morning, I thought to check-in on-line for our 16h30 flight to Lanseria, just to be advised that those flights have been cancelled due to the "no show" on Friday morning. So I had to pay in an additional R1 732.80 to be on the same flight back as originally booked. Due to unforseen circumstances, and an inconsiderate lady that assisted us at the check-in on Friday morning, this weekend has cost me an additional R5 732. I am sure that if she really wanted to help us, she could have. I am utterly disappointed in Kulula at even with my Discovery discounts I get when booking, I will NEVER fly Kulula again.