You can reply to the notice on your own.
Simply you can deny all the allegations in clearly worded 'denial of all allegations'
i.e. "all the stated assertions which depict and impute that you have some something wrong or you are blameworthy' are frivolous, untrue and false and rather they are defamatory, and you are not liable for any costs for any notice whatsoever.
Send it to the lawyer by RPAD and also a copy to your spouse by RPAD. and just wait!!!!
Don't give your explanation or defense at this time.
else they would come up with some other allegations!!!! while filing the suit!!!
Also do not make any counter allegations.
Just say you have utterly hurt and depressed and disappointed.