Just so you understand, a power of attorney ("POA") is a document by which one person (the principal) gives another person (the agent or attorney-in-fact) the authority to deal with third parties on behalf of the principal. There is no such thing as having "[p]ower of [a]ttorney over" another person. A POA may be very broad or may be extremely narrow. For example, I could give the woman who sits outside my office authority to handle all of my financial affairs, or I could give her authority to handle only a single thing (e.g., the sale of my car). In your case, I suspect that your parents gave the friends' family a POA to make medical and educational decisions for you that your parents would otherwise have exclusive authority to make.
What does "all requirements for emancipation" mean? In other words, the laws vary (sometimes greatly) from state to state and you didn't identify your state (despite having been prompted to do so when you posted).
I'm not sure what "worth it" means, and no one here can make value judgments for you. Keep in mind that, while laws vary from state to state, it is generally the case that a minor seeking to be emancipated must have parental consent and the demonstrable ability to support him/herself without any assistance from anyone else. Since it sounds like you lack the ability to be self-supporting, it sounds like any consideration of whether it's "worth it" is moot.

