Well, then you're talking past me. Christian, bad Christian, good Christian? She's not a believer.
Then you and I have a different opinion on what a good Christian is: He lives with an unbeliever, holds grudges, both against biblical mandate, but you cannot say he's not a good Christian, or, that this lifestyle isn't being a bad Christian. I suppose ones standards need to be Biblical.
She doesn't owe him asking for forgiveness, she has sinned before God and unto God, not him. Psalm 51:4.
I'll put it this way, such a lifestyle would receive church disciplinary measures by any conscientious and biblical church. I would then consider this a bad Christian example because plainly it is. I wouldn't lower that standard to philosophical arguments.