Legal Question in Civil Litigation in California

Send her an email stating that you are sorry for flirting with her husband and that you don't wish to be contacted by her again. Tell her that you feel threatened by her unwanted communications that you will filing for a harassment restraining order if she contacts you again or follows through with any of her threats. Block her on Facebook and report her for the unwanted contact. If you hear from hear again, take her to court. Keep copies of all messages she has sent you.

That's a tough call. It's not really a legal problem. You probably have a right to a civil harassment order, but sometimes that's just gasoline on a fire. It's never an easy thing to figure out if ignoring the person will eventually make them go away (probably the best thing in a plurality of cases), sending them a mature apology, promise to never contact them again, and contrite request to be left alone will do the trick (sometimes works with people who get worked up over being ignored until they get some form of vindication), or if legal action is necessary because the person has really just "lost it." The one thing I would not do at this stage is threaten legal action. Just do it or not. The only time I would threaten legal action would be if the contrite apology and request that the matter be put in the past is disregarded. Sometimes a follow-up, "look, I've tried to be adult, I'm sorry for what I did, this needs to drop or I'll have to go to court" message is effective at that point.