The patient’s right to refuse treatment must be respected, even where doing so may result in permanent physical injury or death. It can be incredibly difficult for medical staff to stand aside and not treat (BMA). Is this applicable in a situation where the patient's partner refuses the treatment?

These are the BMA's guidelines in a situation where a patient refuses to receive treatment:

"In a situation like this, there are ways to allay the patient’s concerns and increase the likelihood that she will consent to treatment. Simple practical interventions, such as introducing partitions into treatment areas, can ensure that patients undergoing emergency treatment feel less anxious and exposed, although this may not always be appropriate in an operational environment for reasons of security. In addition, by keeping in mind the overriding need to respect patients’ dignity, doctors are more likely to recognise behaviour among their colleagues, which may compromise dignity, and to challenge such behaviour",

This means that you can also offer alternatives to her husband by offering that he attends the surgery if possible? Or by illustrating the worse case scenario if his wife doesn't get an immediate treatment.

Of course, the issue may be presented in a different way – see Queen of Spades