I agree with Mr. Pines; report the matter to the police without further delay, and do not post anymore facts about your situation on this public website or anywhere else on the Internet, including social media like Facebook. I would also recommend that you explore counseling to help your deal with your trauma. Burying it is not dealing with it, and needing help is okay. Good luck. Btw, because of the sort of "family" nature of the possible perpetrator I would not mention this to anyone or that you are reporting it to the police.
Generally there is a statute of limitations on rape, but this was child molestation, as well, and as you were the child, once you attained the age of majority you have the right to pursue those charges for a limited period of time after reaching 18. I'm not certain of the process, but you may want to start at a rape crisis center. They should be able to offer counseling and may even have some contacts with the local authorities or the prosecutor's victim assistance counselors that could help you through the process. I believe it needs to be pursued in the county where the incident first took place. Hopefully, pursuing the matter will provide you with some closure. Good Luck
This is not intended to be legal advice or create an attorney-client relationship. If more information is needed, you should consult with an attorney in your state regarding the specifics of your situation and the options available to you.