No - a separation is no longer necessary in New York. Child support is calculated based on a percentage of the non custodial parent's income. Spousal support - what is often called alimony - requires a more complicated analysis.
If the court finds that she could be working and isn't, the court can impute income to her in the amount that the judge feels she should be making. That will not materially alter child support but certainly would have an impact on spousal support.
§ 170. Action for divorce. An action for divorce may be maintained by
a husband or wife to procure a judgment divorcing the parties and
dissolving the marriage on any of the following grounds:
(1) The cruel and inhuman treatment of the plaintiff by the defendant
such that the conduct of the defendant so endangers the physical or
mental well being of the plaintiff as renders it unsafe or improper for
the plaintiff to cohabit with the defendant.