She screwed herself. You're not responsible for what could happen to her. She screwed you. If you file a police report, the state will help you get a divorce, because she's a bigamist. There is no divorce. Tribal courts are useless, unless you're an Indian. Even if you could pay for a lawyer, she'd still get in the trouble that she deserved. So, if you want no trouble for her (or to have her face justice), you can just keep your mouth closed. Legally you are still married to her, and she isn't married to him. This is her mess. Only the government can clean it up now. Post your email in your reply and we can communicate that way.