I'm going through a fresh Windows installation as we speak, even though my computer looks safe so far, as no antivirus can detect any kind of malware right now.
If you can, install Linux OS as well on your PC and use it only to install wallets, performing transactions and maybe trading.
There are fewer chances of picking up malware via Linux unless if one is way too careless. I have mine and I have never ever felt unsafe like I do when using Windows even though I have not many random apps installed in it.
Antivirus software programs are just bullshit and can give you a false sense of security.
I've only used Ubuntu once, quite a few years ago, and it's a completely different environment that I couldn't get used to. However, they're definitely safer and ideal for such applications, which makes me consider it, especially now that I've installed a second HDD, one of which could be Windows and the other Ubuntu. It'll only be isolated for the wallet, which would make it a lot safer than it being on a Windows environment that's been used at the same time.
awareness is the key when transacting, you have to not only double check but triple check on addresses, we never know if we have this, even if we have these popular antiviruses.
Antiviruses is easily bypassed if the scammer/hacker is good enough at creating a program not to mention they most likely hitch these programs on legitimate programs that's downloaded illegally. Trojans work that way and they install themselves without you noticing them.
Hopefully OP reported this crime at the least to the cybercrime division of OP's country because hackers aren't scared because no one reports them even if it's left unchecked at the least they will have a record of this incident so when more people report similar situations, they can just act on it. I do download movies and animes in my phone so these scares me big time but this helped me remember to always double-check the address that I will transfer my funds.
Antiviruses can be bypassed when it's a new type of malware or virus. After user reports, they update their software to include such malicious attempts. Back then, there wasn't a single mention similar to my case, so I guess I was probably one of their first victims. Reporting to the authorities wouldn't change a thing; I had no details other than a wallet's address, and while the amount I was scammed was petty for them to even bother, they'd laugh at me if I reported that my 25 XRP coins, then worth about $10, were stolen due to a fake extension.