First, here's what you have the right to expect from your company when it investigates the complaint.
An employer should conduct a prompt, thorough, and impartial investigation. As soon as management learns about alleged harassment, it should determine whether a detailed fact-finding investigation is necessary. If a fact-finding investigation is necessary, it should be launched immediately. The amount of time that it will take to complete the investigation will depend on the circumstances. If for example, multiple individuals were allegedly harassed, then it will take longer to interview the parties and witnesses.
The investigator should interview the employee who complained of harassment, the alleged harasser, and others who could reasonably be expected to have relevant information.
Before completing the investigation, the employer should take steps to make sure that harassment does not continue. If the parties must be separated, then the separation should not burden the employee who has complained of harassment. An involuntary transfer of the complainant could constitute unlawful retaliation. Other examples of interim measures are making scheduling changes to avoid contact between the parties or placing the alleged harasser on non-disciplinary leave with pay pending the conclusion of the investigation.
You may feel that these guidelines favor the person complaining of harassment; however, you should understand that the company could face a serious lawsuit from the person who complains if it does not investigate the complaints promptly and thoroughly. Therefore, many companies take initial complaints very seriously, even if they are later proven to be either untrue or incapable of being substantiated, so you should view a thorough investigation as an opportunity to prove your innocence, rather than as a presumption that you are guilty.
For the protection of both the complainant and the person accused of harassment, information about the allegations and any records of the complaint of harassment against you should have been shared only with those who need to know about it. You should seek assurances from your employer that it will keep information about the complaint confidential, and will ask all participants in the investigation process to do so as well.
You should also be aware that some companies, to reduce and/or prevent lawsuits, have adopted a zero tolerance policy where all harassment is concerned, which has led to employees being disciplined or terminated for conduct that was previously tolerated at work. So, it is probably wise to realistically assess your conduct to determine whether the complaint may have any merit at all, even if some allegations are either untrue or cannot be proven. Even if your conduct does not get you in trouble this time, it may in the future.
You may also want to consult with an attorney at this point to discuss your participation in the investigation and to determine whether you have any legal remedies if the company does take any action against you for harassment.