
    Amy Rauchway, Appellant-Respondent, v Bernard Kotyuk, Jr., Respondent-Appellant.
    [680 NYS2d 361]
   —Order unanimously modified on the law and as modified affirmed without costs and matter remitted to Supreme Court for further proceedings in accordance with the following Memorandum: Following a nonjury trial in this divorce action, Supreme Court erroneously dismissed the complaint alleging defendant’s cruel and inhuman treatment. Plaintiff testified that defendánt told her in 1991 that he was engaged in an extramarital affair. Defendant admitted that he has been engaged in an extramarital affair since 1991 and that he refused plaintiff’s request to return to the marriage. Evidence that one spouse is having an extramarital affair with the knowledge of the other spouse is sufficient to constitute cruel and inhuman treatment (see, Hay-dock v Haydock, 222 AD2d 554, 556; Guneratne v Guneratne, 214 AD2d 871, 872). Moreover, expert medical proof cdncerning the effect of that conduct on plaintiffs physical or mental well-being is not necessary (see, Guneratne v Guneratne, supra, at 872). In light of our determination, we do not address the remaining issues raised by plaintiff.

The court properly dismissed defendant’s counterclaim seeking a judgment of divorce based upon plaintiff’s cruel and inhuman treatment. Although defendant testified that plaintiff left the marital residence in December 1990, the record does not establish that she did so without defendant’s consent.

Thus, we modify the order by reinstating the complaint and remit the matter to Supreme Court to grant a judgment of divorce in favor of plaintiff (see, Lewis v Lewis, 227 AD2d 908) and to determine the remaining issues by trial, if necessary. (Appeals from Order of Supreme Court, Oneida County, Grow, J. — Divorce.) Present — Pine, J. P., Lawton, Pigott, Jr., Callahan and Boehm, JJ.  