Yes.

Abuse would show itself, if it occurred. Then, it would stop, of course.

I would support/squash by talking to her and listening back.

If not sexual by their choice, I would defend their openness and tell everyone else to fn mind their own business. If it was sexual, I would worry myself sick that someone besides myself would find out. The 'talking to her' would be more urgent.

Pretty simple really. But, due to current stigma, it would likely be very stressful for everyone involved and best avoided if possible. However, sometimes love will not take no for an answer.