In order to file for separation or divorce she is going to have to serve her spouse with a summons and complaint. Therefore she will have to locate him. She should try to locate some of his relatives or friends and see if they know where he is.
If she is living in the New York City metropolitan area, please have her call me at 212-370-1660 to discuss mediating her divorce.
Leonard M. Weiner, Esq. /Divorce Solutions