A gmail account (not mine) is forwarding spam to my Apple email account

A gmail account, that is not mine, is forwarding spam to my Apple email account. The gmail is the same as my Apple account, but with gmaill.com instead of me.com/icloud.com. Clearly, I didn't authorize this email forwarding. Apple can't do anything about it since it's occurring from the gmail.com. Suggestions on how to get it to stop? Can I demand that Google stop the forwarding or delete the account? Any other ideas? It's accounting for about 1/3 of the spam I'm receiving.