She was a very manipulative and neurotic ''breeding mare''
That Royalty needed to introduce new noble blood.
She couldn't understand that, and the historical role that the 'married-ins' were supposed to play: bear kids, STFU and smile.
THEN she started playing dangerously childish media games and, fatally, started threatening to reveal a few royal dark skeletons and mess with CIA aka the US's Foreign Policy (re landmines)....
All the above = ''suicided''.