I was married in 1999 to a man who had several girlfriends on the side that I did not know about before marrying him. We were only living together for 6 months, the entire time of which he was cheating on me. When I found out I confronted him and he moved out and I have not seen or heard from him in 10 years. A woman called me a few years ago and asked me if I knew him and I told her yes. She then told me that she had just gotten married to him and I told her that I was still married to him. She then hung up on me and I have not heard from her since.
My question is: Because of the situation, would I be eligible for an annulment or would I have to get a divorce from him?

Editor's Response
If he was married at the time he married you (and you did not know it), then I would say your marriage is void. Technically, with a 'void' marriage, the parties do not need to petition the court for an annulment, because, by definition, they never were married. However, to create a paper record and to ensure that the state no longer considers the marriage valid, it is a good idea to file a Complaint for Annulment.
If he was not married when he married you, then your marriage may still be valid, and you will have to petition for divorce. The other woman's marriage (the one who called you), however, may be void. In any case, I would consult an attorney if you can, because this is a complicated situation. Good luck.