Your friend has to be somehow liable for your injuries. You may have a worker's compensation claim if he paid you. Otherwise, you can always try small claims.
You should contact a personal injury lawyer in your jurisdiction for advice. You can run a "find a lawyer" search here on Avvo to locate personal injury lawyers in Hawaii.
Were you his employee or merely doing him a favor? Assuming the latter, he is likely responsible for your injuries and you ought to seek out a personal injury attorney in your state to review all potential legal remedies.
The author of this answer is an Attorney-at-Law, licensed to practice law only in the state of Arizona. Unless both you and the author have signed a formal retainer agreement, you are not the author's client, and the author's discussion of issues does not constitute legal advice. Opinions expressed herein are solely those of the author, and are neither privileged nor confidential.
This type of change of heart by your friend is pretty common these days, so I wouldn't take it personally. The time deadlines for pursuing a case have probably not passed. If your friend was negligent (you have not really provided any facts from which this could be determined) and if he has homeowner's or renter's insurance on that house, then the insurance should cover him for any liability that he might have to you. You haven't really provided the basic facts about what happened to make it possible to determine if your friend was negligent nor if such negligence was the legal cause of your injuries. A free consult with an Accident Lawyer in Hawaii might help.
The information provided in this answer is intended to be preliminary and informational ONLY. It is not legal advice for your jurisdiction nor may it be relied upon as such. The posting of this informational answer does not establish an attorney-client relationship.
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