One thing you might want to explore is this:

&gt;She fell in love with her married friend  
&gt;  
&gt;The man and his wife had not previously been open or poly. They had been having marital problems  
&gt;  
&gt;She claims she's poly  
&gt;  
&gt;has basically dated this guy exclusively for a year while he stays with his wife  
&gt;  
&gt;She's had a least 4 other serious, long term, monogamous relationships  
&gt;  
&gt;To me, it feels like a very extreme lifestyle choice that she never gave any indication of wanting.

She's not poly. She bought into that narrative to be able to justify being with this dude until he separates from his wife.