Australian workplace laws provide basic protection and entitlements for all workers in Australia including workers from overseas, such as international students and temporary visa holders.
You may get to start over and reapply for the visa in some cases, but in most cases, you don’t get to re-apply and may face up to a 3-year re-entry ban.
To apply for an onshore Partner Visa (subclass 820/801), you must be sponsored by either your de facto partner (with whom you have had a relationship for 12 months or more) or your spouse.