Hi thunderbear,
Largely agree with other posters. I have Crohn's and bipolar II.
Prednisone can mess with your mind. Is the doctor open to trying other meds? Please talk to the doctor about this right away. If the doctor doesn't want to talk about the mental side effects of Prednisone, get another doctor.
I am surprised at the doctor's statement that the Crohn's could kill your husband within a year if he doesn't improve his lifestyle. Crohn's is an awful disease, but often manageable. Even smoking and poor diet shouldn't
kill him in a year, I wouldn't think. Is there something else bad your husband is doing?
Please be careful with your husband's behavior. I believe you when you say he does not mean what he is doing, but that just means he's not fully in control of his actions, and that's risky.
If you are in the US, please check out CCFA for support recommendations.
http://www.ccfa.org/
Good luck.