As long as you don't have anything in your profile that she could use to track you online or to get ahold of your personal information, I wouldn't worry about it too much. Be warry of her as a trouble making person but, don't let her frighten you. Bullies love fear. They search for it and if she's anywhere near as bad as you say then she is probably just looking for prey by checking out different people that she has clashed with in the past.
If she starts harassing you then, leave the forum and if after that she tries to stalk you, let me know and I'll try to help you out as I have been stalked and harrased online before and know some of what to do and what not to do.