I currently have charges pending against someone for forgery and embesselment. She will be reprensented by an attorney that I have used in the past.

Only if the attorney represented you on any matters involved in this criminal case. Otherwise, no conflict.   The preliminary hearing is a hearing to determine if there's enough evidence to go to trial. Sometimes the defendant waives his right to a prelim if it benefits him in some way. Otherwise the district attorney (or arresting officer) will ask you to tell your story to the judge and the defense attorney has the right to cross-examine you. The standard of what the judge is looking for is low--was a crime committed and did this person likely commit it?