Cancelled flight-appalling treatment to the sounds of Maria Carey’s Christmas Carols

Travelled Darwin to Adelaide with Jetstar Jetstar airlines on the JQ84 Darwin to Adelaide flight 19/12/17.
Following check in, around departure time, we were informed that the flight had been cancelled
as I understand for lack of of a single member of flight staff.
We were at that point instructed to go back to the check in desk on the ground floor.
This announcement was followed by a mad rush to the Jetstar desk and the formation of an long line of disgruntled passengers. At no stage whilst we were in line were we advised of what was happening. Through a process of Chinese whispers we came to understand, incorrectly as it turned out, that alternative travel arrangements were being made. Those at the front of the line- the more fleet footed, those without children and I suggest the more seasoned Jetstar travellers had the choice of the few good travel options. Law of the jungle it seems.
No one made any enquiries as to the well being of anyone in the line. There was no management at all of this process- the elderly and infirm (including a man in a wheelchair), families with babies and young children, those with connecting flights were not bought to the front of the line. No additional staff presented to assist with the workload. The cue moved extremely slowly with those at the back spending hours in line.
An added special torture was Maria Carey Christmas carols over the PA system.
Upon arriving at the front of the line I was advised of travel options and selected an evening flight from Darwin, overnighting in Melbourne and arising at what, with different time zones, would amount to 0330 Darwin time to catch an 0600 Melbourne Adelaide flight- a poor alternative necessitating organisation of accomodation for which I was not offered assistance or financial compensation. My discussions at this point led me to understand these flights had been booked and I left the airport a little over four hours after the planned departure of our flight, exhausted and disgusted about the unprofessional, heartless, contemptuous manner in which I along with all the other aircraft passengers had been dealt with.
Upon making further enquiries following my return home I discovered that no flights had been booked and I had indeed spent hours in a cue simply to be advised of some travel options. Unbelievable.
The process of making alternative arrangements was needless to say painful. In the course of making these bookings I was further advised of a Jetstar flight leaving Melbourne at 0820 for Adelaide which I had not been earlier advised of- as if is it not obvious following a late arrival in Melbourne I might prefer not to have to get up five hours later instead of seven and a half.
I travelled Virgin airlines to Melbourne that evening-the contrast in care was obvious.
On my Melbourne Adelaide 0820 Jetstar flight the following day I was placed in the rearmost seat without a window and overhead luggage space- a nice touch for a disgruntled customer.
I have made a formal complaint-I have zero confidence this will achieve anything at all.
I will never, ever, ever travel with Jetstar again.
How on earth does this airline continue to remain in business.