Forgot Gmail password

I can't remember my gmail password to my main account with all my information. I have tried retrieving it with no luck. I do not have access to either of the mobile numbers on the account. The phones belonged to my husband and me, they were both stolen. I used his email as a backup email. The email was removed. It gives me the option to use his email, sends the 6 digit code, then tells me the account can't be verified. How can I recover my password? Why can I get as far as the 6 digit code but no farther? Please help me?