Learn about cults!!!
Your daughter and her husband are under the influence of mind control. That is just a real fancy way of saying that they are in an environment where everybody thinks the same way, and uses the same stupid arguments to control them.
So what you need to do first is to learn about mind control cults. Here are a few links: http://www.freeminds.org/psych/lifton.htm http://www.rickross.org/mind_control.html
I would recommend the following books:
Releasing the Bonds by Steven Hassan
Combatting Cult Mind Control by Steven Hassan
If you don't like to read you could order these videos:
http://www.rickross.org/dvds/dvd.html
Hope this helps! Take care mom. To answer your question, there is always hope! Many here have left, or have helped others leave. I'll be prayin for you!
CYP