Miss F, bide your time, reapply and use the time to better your position as an applicant (eg what areas were a bit thin on your resume- experience? Skills?)
If you do go for other airlines, as a fellow Aussie I would say AVOID Qatar. I know many who went and none of them are happy. It is too restrictive for those of us who grew up with the Aussie way of life. Every single Aussie I know in QR couldn't wait to get out. And once you work for them, you must wait 12 months before you can apply for EK. Keep this in mind.
CC380- if they say no, they say no. Not much you can do. I have met a few rejoiners recently, but I think almost all left due to illness or death in the family...