As far as I can tell, where I live, there is no one independent who can (or is willing to) give advice to councillors. Generally speaking, the Chair and Clerk hold the line between myself and advice from our county body, and only a well put complaint based on the code of conduct will gain me access to advice from the district monitoring officer. Of course without an upheld complaint, advice does not need to be taken on board by anyone, and bullying is a difficult one to land. You are expected to suffer all manner of indignities because you offered yourself for election and so must expect the cut and thrust of debateā¦
You may have more success in a complaint if you can demonstrate that he has broken the code of conduct in other ways as well as bullying.
Having said all this, I know that there are some colleagues on this site who have a different experience of their Monitoring Officer and it may be worth finding out how open they are to giving you some support.