How do I get my friend who is 18 out from a mental asylum?

Alright, long story short is that my friend got married at the age of 18 to my other friend. From there, they lead a perfectly happy life until the my friend (we'll call her Angela for now) as taking away and dragged into a mental asylum. As far as I know, she's mentally stable. What can I possibly do to help her? Is there anyway I can let her know that she can get out?