Sounds like they are weak Dubs. The kids that left probably faded and never disassociated or got disfellowshipped. My brother faded and my parents still associate with him. If she is dating a worldly guy "you" then she is definitly not in good standing. A young guy got "marked" at my last hall for dating someone who wasn't baptized. This means that other witnesses would only hang around him at the meetings. No extra association. They stuck thru and eventually got married though.
Is your lady baptized? Does she believe it's "the truth"? If she is awake but only stays in for family reasons then there may be hope.