My iTunes downloads were made using my old gmail address. I had to quit using this email address as it got hacked. I created a new gmail account. How can I get my iTunes downloads into the new gmail account?

My iTunes downloads were made using my old gmail address. I had to quit using this address as it got hacked. How do I get my iTunes downloads into my new iTunes account that was created with a new gmail address? In my old iTunes account (with the old gmail address, I can't 'update' my email address or even 'add an alternate address' as I had already created this gmail account and inputting the new address into iTunes gives me the 'pop-up' that 'this account is already in use.' Advice please!