Deleted email account??

About 6-7 mom ago my ex-husband (unbeknownst to me) canceled what was once our shared internet account when he moved in with his affair partner. For personal safety and privacy issues, I had mostly switched my personal emails to an email address unknown to him. I had some very important information that I had stored there that I will most likely need for a possible court date in the future. Is there any way to get the email addresses back? My name and email address was the primary on the email accounts, but his name was the last one on the internet bill. I desperately need this information back if at all possible. The only reason I found out was when I tried to log in to my email to show my attorney something, it wouldn't pull up my email account. I still have my own personal ATT wireless account and have had ATT since 1993 so I'm hoping someone can possibly help me!