Can My New Husband's Ex Ever Access My Money?

No. You have no obligation to her. You might want to keep your finances separate just in case the ex-wife tries to renegotiate her alimony, but that seems incredibly unlikely.

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Harry S. Margolis practices elder law, estate, and special needs planning in Boston and Wellesley, Massachusetts. He is the founder of ElderLawAnswers.com and answers consumer questions about estate planning issues here and at AskHarry.info.