And the article also said:

Psychotherapy and PPD
If the patient will submit to treatment, psychotherapy has been the most promising treatment method for those with Paranoid Personality Disorder, and can be useful in helping the patient control his or her paranoia. Group and family therapy, not surprisingly, is not of much use in the treatment of PPD due to the mistrust people with PPD feel towards others.

As personality is a relatively stable, deeply rooted aspect of self, the long-term projection for those with Paranoid Personality disorder is often bleak. Most patients experience the symptoms of their disorder for their entire life and, in order to manage their symptoms of paranoia, require consistent therapy (Dobbert 2007, Kantor 2004).

For one thing the article is about individual therapy. If ACanthony could convince her to go with him, who knows what would happen? To take a chance on joint therapy may not change anything. Just the same, the other suggestions that have been made lead to a married but separate relationship.

I do not intend to engage in a debate with you. To do so would not be offering information and support as the Guidelines require.

Good luck in resolving this, ACanthony. I wish you the best.