This is some advice I learned from a dear elderly friend about how to extricate yourself from just about anything.
Tell her that as honored as feel that she has placed her confidence in your advice, that you are beginning to understand that your level of expertise is insufficient to meet her needs, and then have handy the name of a professional for her to reach out to. Then each time she pushes you to engage, politely decline and repeat that you just don't feel qualified and wouldn't want to steer her wrong and then change the subject.
This works well for folks who want to use you as a release valve for their problems or worries so that they get relief enough to not actually act on a path towards a solution for their problem.
