You need to remove the emotion from the equation. First step is to WRITE (pen and paper) and put down a short but clear description of the issue. What has been discusses and what outcome you want. Send that to:
Customer Relations Group, PO Box 306 Salisbury South 5106.
You should get a reply in 2 weeks, an official complaint number and hopefully a good outcome.
If you are still not happy you can then move the complaint to the TIO which will work on your behalf to sort out the issue with Telstra.
If you'd like, tell us the problem and we can possibly provide some direct advice.