What should I advice my friend about how to keep her relationship with her fiance strong amidst crisis?

Her fiance has been falsely charged in court and is out on bail. He is not the usual sweet guy- and now, most of the time, quiet and won't open up. I told her to be supportive of him but sometimes, he just does not want to talk.My friend fears this crisis will strain the relationship so much.. What can I tell her to do so their relationship survives.