Ask an Immigration Solicitor. Get an Answer ASAP.
i can help you for your concerns.
you can inform to Home Office about your broken relationship.
i have attached the link
please read it carefully.
Home Office will take steps to cancel her visa.
i hope it will help you
Please give positive rating.
You should read the first line of this link which addresses the both sides.
This link explains further to that party who is dependant of a British citizen.
I hope it will help you