There are a lot of issues here. First, in what manner did your attorney "drop" you? Did you sign a substitution of attorney? Did he file a motion to withdraw as your counsel of record? Not sure what "by his secretrary's word" means. If he is still technically your attorney, you can simply fill out and sign a substitution of attorney form and send it to him by mail or fax. He'll then sign it and file it with the court. You do not need to speak with him to fire him. Second, your reference to your spouse having an affair -- California is a no-fault state. The fact that your spouse had an affair is not relevant. I would not fault your attorney for not using that information in court. Three - false claims of DV is very serious and unfortunately, not uncommon. Find yourself a new lawyer and move on. If your new lawyer can establish that your former lawyer made a mistake or failed to properly represent you, maybe you can get the Order of Protection set aside or otherwise dismissed.
You have many questions but it's very obvious you need a new lawyer. Fire your old lawyer and get a new lawyer to represent you zealously within the bounds of the law.