Every time a perp’s girlfriend goes thru something like this, we need to appreciate how our ancestors frowned on loose sex outside of solid marriages. The girlfriend must have been totally unable to discern men of good character.
Oh, heck, a significant % of women, even some with considerable raw intelligence, prefer “bad boys”. Our ancestors’ mores helped tamp that down, but, it’s always been true.
To be fair, it works the other way too (guys who prefer “bad girls”). Probably more so.