The thing is, perhaps her marriage is happy. But her dark secret is known and will become known by more people over time. Does she want to let this thing fester or better to face it straight away.** The way I see it, her very life could be in danger here **so she needs to think very carefully about what to do and how to handle it.
You nailed it. This can be a bitter reality too. She and others around her who know have to be careful about all . This two lives are depending on this secret now.