Some email sites will shut down an account for many different reasons. I had one shut down because I hadn't used it in ages. But there are other reasons and since I don't know you, I won't speculate.
I have never liked AOL and this is just another nail in their coffin as far as I am concerned. Hopefully you have a list of email addresses of all the people you correspond with. If you do, I would suggest you find another email client like outlook, yahoo, gmail, or whatever suits you. I use one at gmx.com for one list of certain people.
Once you have settled on another email client, make sure that "renalegg" is available. If not, it should give you some alternatives. Choose one and make it yours. Next, create a list of all your email recipients and either just add them to your "contact" list or create/compose an email and place all of their addresses into the Blind Carbon Copy (BCC) section and in the "To:" section, put your new email address. Yes, you can send yourself an email with most clients. Send the email to your people explaining what happened and that they should start using your new email address.
The reason for the BCC use is to respect the privacy of anyone on your list of friends who doesn't want their addy spread out over the Internet.