First of all, it is highly likely that it is NOT too late to do anything. Second, if what you want is jail time, then you need to go to your local county or city prosecutor to discuss your situation and find out whether or not what occurred was actually a crime in your state or city, because the law is different around the country and you need to know for sure what it is where you are. Last, if you want to recover money for what occurred, then you should immediately see a local Personal Injury attorney near you. Call your local attorney Bar Association and ask for a referral to a local Personal injury attorney right away. But act quickly because for every legal right you have, there is only a limited amount of time to actually file a lawsuit in court or your rights expire (it's called the statute of limitations), so don't waste your time getting to a Personal Injury Law attorney and finding out what your rights are.
The first question you must ask yourself is "Do you really want to go into a court of law, while a jury is looking at you, and describe the events that took place when there is no insurance coverage to compensate you should you prevail?" If there answer is "yes" see a local lawyer to discuss what options may be available in your state.
You would have to speak to a criminal attorney regarding possible criminal charges against the family friend. As far as your civil claims, you may have a claim for battery as well as other claims. It sounds like your ultimate goal is to make him pay you for the damage he's caused you as a result of contracting an STD. The problem is that a lawsuit may not accomplish this goal given he has no job and no assets. Even if you file a lawsuit against him and a jury awards you a million dollars, the judgment isn't worth the paper it's written on if you have no way of collecting any money from him.
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