No attorney will be able to advise you specifically as to your chances of reopening an agreement or judgment without reviewing and without reviewing the transcripts of hearings.
Under the rules governing the conduct of attorneys in New York it may be necessary to remind you that this answer could be considered attorney advertising.
Settlement (opting out) agreements are extremely difficult to overturn. The passge of 7 years makes it even harder. I would also caution you to not be so quick to act on the advice of well-meaning friends or relatives as they often don't understand all of the facts of your particular case. Every case is unique and your attorney is (or in your case was) the best person to advise you as to what to do. If you are having second thoughts, you can speak to another attorney to review your case and maybe put your mind at ease that your decision to sign the agreement was best for you at that time.
It is hard to know from the facts as you present them, but the caselaw makes it difficult to overturn such agreements the longer you wait - the passing of seven years means you have lived under these terms for seven years and is a heavy factor against you. Really, you should consult some attorneys to see if there are other factors that may outweigh the passage of time.
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