If you believe in equality between the genders and you intervened to ensure the safety of a woman - then I would argue you are the feminist in question. Might not feel like it, you might not enjoy the label... I certainly don't, but you effectively intervened in a way that made the situation equitable and neutral.

You didn't blame him. You didn't blame her. You couldn't solve the problem - but they both have equal say in the continuation of their shitty relationship. The issue worth exploring is which one of them requires psychological input to resolve this relationship in a way that is beneficial for both.

That ain't an easy fix. :o)