Defamation is an extremely difficult case. For any one to evaluate your potential suit, more facts are needed. Specifically the contents of any alleged statements. Also, statements that are a person's opinion are not the basis of a defamation suit.
If you have copies of those statements and your divorce attorney either does not want to pursue such an action or does not handle those types of cases, many local (county) bar associations in California operate a referral service. For a small fee to the service, an attorney that handles that type of case will give you an appointment for 30-45 minutes.
Also, you might just ask yourself if you want to or can maintain the membership. It sounds as though your divorce is very animostic and your soon to be ex is going to stay with his old buddies who are going to stay with him.
I am not a Moose/Elk and do not know if they now have female members. If they do, why not transfer your membership to another lodge. Staying where you are is certainly not going to be pleasant.
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