I need help, I am being hacked.

It seems very unlikely that two different servers (Google & Blizzard) are compromised by the same person unless you've downloaded something or are using the exact same login information on both accounts. As @Lucyna suggested, change your passwords first and foremost, maybe even the associated email of your BattleNet account as well. Both Google and Blizzard support Two-Factor Authentication that you can tie to a mobile app or SMS text. I would recommend exploring those options for added security from unauthorized logins.

Secondly, if you are playing D2R online, your character save shouldn't be local and nobody should be able to edit your save. Are you sure your gold and items are not appearing on different tabs?

That's not exactly an indication that you are being hacked. There are no hacks that exist that can login simultaneously to Blizzard's servers and remove your gold while you play, unless you are playing the game offline on a local save and the file is somehow modified during use. If people had the capability of removing gold/items from an online D2R account, we would see widespread reporting of the issue.

Either way, this is something you will need to file a ticket through with Blizzard. They should be able to investigate your account and determine if unauthorized access is occurring. If you think something is manipulating the files locally, I'd recommend getting a virus/malware scanning software such as ESET or Malwarebytes and run some scans to see what they find.

Something to keep in mind about hacking is that it's not as common as TV or movies make it out to be. Most "hacking" is simply phishing or using compromised account credentials that are available online after big data breaches. People with the skills & hardware required to actively hack accounts or exploit security flaws wouldn't waste their time removing items/gold on Diablo or hacking into a random Youtube account. They typically want a return on investment for their time. It's far more likely that something else is going on here and I would recommend starting with making sure the system is malware-free and that your accounts are protected with additional security layers such as 2FA. At the very least, 2FA would warn you of potential login attempts.