This is good Charlatan, time heals wounds, the fact that she said that she doesn't know if she can live with him not trusting her. Rather than that she should be working to build that trust. Perhaps tell your friend that he should inform his wife that trust will become part of their relationship, but it will just take time. If he feels that he won't ever be able to trust her, than I don't think they should really continue, trust is the basis for any relationship. If they truely love each other it can be mended though.
Hope it all works out for the best
