Yep. My brother started dating his current wife before his divorce was final -- because he & his ex lived in North Carolina, where, as your sister found out, you have to legally separate for a year before you can even file for divorce, and then, depending on various factors, the divorce itself can take a long time. He met her after the divorce was initiated but had been dating her more than a year by the time it was finalized -- over 2 years after he & his ex decided to end their marriage.