First of all, all it takes is about $100 (filing cost and service of process) to file to reopen a divorce case and anyone willing to plunk down their $100 can “take you back to Court.” Prevailing is a horse of a whole other color.
While your approaching marriage has clearly angered your fiances’ ex wife, and while there is an odd argument to be made, I would be skeptical that the argument would succeed. The basis of the argument is that it is much more economical for two to live together. Literally that the Court should treat your contributions to the bills of the household as payments “in kind” to the Husband’s benefit, reducing his cost of living and therefore “freeing up” his discretionary funds from which more support could be taken.
In reality, the ex wife would have a very hard row to hoe. Unless the Final Judgment of Dissolution of the marriage literally found there was not enough money for enough alimony to meet all of the proven needs of the ex wife’s (or unless there has been a substantial change in your fiance’s income), the ex wife would have to prove that her needs have changed and are not being met under the current order. Once she proves that, then the Court has to find the former husband has the ability to pay, or meet, those increased needs and that is where the argument your contributions to the household expenses should be treat as “income” to your future husband.
But for that tortured theory, your income should not be considered when a Court examines the ex wife’s need or the ex husband’s ability to pay.
Courts normally do not consider the income of the new spouse in calculating child support - just the natural mother's income and the natural father's income. Your fiancees' ex is jealous and trying to prevent the two of you from getting married. Don't let her do that.
The information provided in this answer does not create an attorney-client relationship and is not considered to be legal advice.
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