I'll put my HR hat on first @Rose18 . Discrimination, bullying and harrasment in your workplace are illegal. Regardless of who you work for in Australia, the National Employment Standards, which underpin all awards and agreements, state that you have the right to a safe workplace and that there must be mechanisms for you to voice concerns or make complaints without fear of recrimination.
Sadly, for all too many people, all that is a bucket of bureacratic mothering statements that are of absolutely no help at all.
Where you work, how far up the food chain you are and your union status can make a big difference when it comes to what you can do, as does the exact nature of the offense. My best advice is to see if your organisation has workplace behaviour/code of conduct/EEO/antidiscrimination policies and if they do, what the process is to make a complaint. That lets you know what you should be able to do. Half the time the people you are meant to report to are the perps. Not helpful.
Before you do anything, start taking notes, copies of emails, records of conversations, the whole shebang. Saying that other people make you miserable won't cut it. You have to able to say who, what, when and where. If you are in a union, contact them, but they will have to have precise details to be able to help you.
None of this stuff is easy to manage, particularly indirect discrimination such as exclusion. Its all about you being able to produce good evidence if you can't trust management to sort it out. People can be such shits.