Does the other board you are referring to have an "ignore" feature? I know some message boards do have them and that they can come in handy. If nobody else is replying to her posts, then it wouldn't mean that anyone was missing out on any of the true conversation of the board by simply ignoring (not seeing) her posts. That way, you don't have to view it...she never knows the difference! Not sure if that will help...but its worth a shot!
Best of luck!