Being the other person in someone else’s relationship consensually is one thing, but being one without realizing it is a completely different one. You might think you’re in a perfect relationship only to find out that you’ve been actively participating in an affair without knowing it. This can be compared to being cheated on as the betrayal and pain are similar in both situations.
After this woman found out she was the other person, she felt crushed and didn’t really know what to do. So she turned to people online for advice, and they delivered.