First, he has emotional problems he has to sort out with himself so he's not wounded by someone's past every time he gets upset.

Second, she has communication problems that she'll need to sort out so she's not asking other people to talk to her husband every time she gets upset.

The fact she used to be a WL is totally irrelevant. Those two problems means that the relationship is doomed to fail even before it starts.

Just tell your friend to enjoy the ride and be grateful for every day that a woman chooses to stay with him (especially one who has had 1000+ men and still chose him) . Tell the girl to be proud of her past and use tap that experience to be strong enough to ask for what she wants from her husband.