OP - do not quit if you are thinking that you will be ok financially because you will be able to prove discrimination and get back pay. Constructive discharge cases are almost impossible to win. If you are at an Executive Branch agency, your agency has an internal EEO office. That is the first stop in the process. They will want to mediate the problem or try some other non-complaint fix. What is important to realize is that this is the pre-step to filing a complaint against the agency. You do not get to file a complaint until after you have finished this step. Do not get confused. If you are not able to resolve the issue through the normal means, it is up to you to take the next step and file a complaint. The EEO officer will not do it automatically and the first thing you filed will not be converted into a complaint. Once you file a complaint the Agency investigates and you will receive a final decision on the issue from the Agency.
If you disagree with the decision, you can then go to the EEOC to appeal the decision or to Federal court. If you choose to go to the EEOC and then disagree with the EEOC's decision, you can then go to Federal Court. (In some circumstances you can go to court sooner -- they cell into play when the Agency or EEOC fail to issue decisions in a timely manner).
Please look a this page from the EEOC's website.
http://www.eeoc.gov/federal/fed_employees/complaint_overview.cfm
Do not quit your job until you have spoken to an EEO counselor at your Agency.