Dear Ms. Tausch,
I would suggest you may want to pull out those by-laws and have the group review them as a starting point. Ask group members to reaffirm that they are in agreement and willing to follow them. If that doesn't work, I suggest you read Chapter 16 in the Community Tool Box on Conducting Effective Meetings. There is a section on handling difficult members, and you may find some ideas in there. Really, the only people you can talk to is your group members. I wish you luck with this.
The Community Tool Box Advisor