NSW I just found a keylogger on my computer

It is not necessarily illegal. Need to keep in mind that the computer may well be considered joint marital property and she do what she likes with joint property.

If ownership is clearly and unequivocally yours, then yes, it is illegal. Can't remember atm if this behaviour breaks Cth or state laws, but it is illegal.

But really it is isn't worth pursuing, and unlikely to be pursued by police. Lock your computer with a secure password, clean it of all other software that is suspicious (there may be more than one package), change all your important passwords, especially email as you will be using that to correspond with your lawyer. You may need a safe or very strong lockable file cabinet for papers.

Good luck, and while things will likely get worse before they get better, remember life will get better if you hang in during the tough periods. Call Mensline for the real dark times.

To start with:
1. Assume that someone with I.T. knowledge is helping her - so don't take anything for granted anymore when it comes to using that computer.
2. Get rid of the keylogger. Don't let be turned into a "tit for tat" or "pot calling the kettle black" issue.
3. Always check the computer before you use it. (It sounds like you may already know what to do here as you already found the keylogger.)
4. If you have the money, get hold of a laptop (even a second hand one) for any sensitive work - don't use the "shared" computer for anything you don't want her to find out about.

If a laptop is not an option, then...
5. Get a portable hard drive and keep it somewhere secure where she can't get to it.
6. Copy any files you don't want her to see to the portable drive, delete the original files and "zero" them. This includes any backups of those files that software or the system may automatically generate. (Google "secure erase individual files" to learn more about this.) "Eraser Portable" and "Blank and Secure" are just two free options that can securely erase individual files.
7. If you must continue using the shared computer, research "portable software" - find out if there are "portable" versions of anything you need that you can keep solely on the portable drive.
8. Learn how to cover your tracks - especially in regard to web browsers which all have horrid security by default.
9. NEVER boot a computer with a portable drive attached. Only connect the drive AFTER the computer has booted and you have checked everything out.
10. NEVER connect your portable drive until you check "Autorun" settings. I advise that you disable Autorun for all removable drives. You can Google how to do this.

I also recommend joining an I.T. forum. Members on an I.T. forum will be able to help you protect yourself even further.

In regard to ownership, she can probably get away with tampering with the shared computer in any way she wants. But if you get your own computer, laptop etc, this all changes:

1. Any tampering in regard to monitoring (installing a keylogger would be just one example), would consitute an offence under s10 of the NSW Surveillance Devices Act; and
2. Any other tampering, depending upon intent, could be an offence under Part 6 of the NSW Crimes Act ("Computer offences").