Thanks for your reply. Your numbered questions 1-6 are more than originally asked in your first post but I will assist.
1) If she divorces and they do no have UK national children the UKBA would curtial her vsia and she should return to her home country. They UKBA are not too great in enforcing this thoguh.
2) See 1 above. Same situation.
3) No, not in terms of matrimonial financial settlement or her visa issues
4) See below
5) No guarantee, no.
6) Almost certainly not.
If there were incidents of physical violence and/or threatening behaviour where she feared being struck by her husband and she reported them to the police then she may be able to make an application for ILR on this basis. The basic requirements are:-
She would have to produce documentary evidence of the domestic violence, statements and evidence of police report/action taken.
She would have to apply using the UKBA's form SET(DV) which is available for download from their website.
There are some guidance notes on the application here:-
If she divorces him and then immediately marries you then she could try and apply to the UKBA for a further spouse visa. She could not apply for ILR on the basis of her previous marriage because it is a conditoin that she is still married to the person named as her spouse/fiance in the original application.
The UKBA would have reservations about your relationship probably and you woulld have to produce documentary evidence corroborating the credibility of your relationship. Technically she would also cease to have leave to remain here when she and her husband consider that they are separated (not actually divorced) so they could conceivably attempt to reject on this basis but I should think that if they accept your relationship/marriage as genuine then they will probably overlook this.
If it is the case that she must return home then she can make an applciation from there based upon your marriage or impending marraige.
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