(b) where he or she seeks to recover possession of one dwelling unit because of immediate and compelling necessity for his or her own personal use and occupancy as his or her primary residence or for the use and occupancy of a member of his or her immediate family as his or her primary residence, provided however, that this subparagraph shall permit recovery of only one dwelling unit and shall not apply where a tenant or the spouse of a tenant lawfully occupying the dwelling unit is sixty-two years of age or older, has been a tenant in a dwelling unit in that building for fifteen years or more, or has an impairment which results from anatomical, physiological or psychological conditions, other than addiction to alcohol, gambling, or any controlled substance, which are demonstrable by medically acceptable clinical and laboratory diagnostic techniques, and which are expected to be permanent and which prevent the tenant from engaging in any substantial gainful employment, unless such owner offers to provide and if requested, provides an equivalent or superior housing accommodation at the same or lower stabilized rent in a closely proximate area. The provisions of this subparagraph shall only permit one of the individual owners of any building to recover possession of one dwelling unit for his or her own personal use and/or for that of his or her immediate family. A dwelling unit recovered by an owner pursuant to this subparagraph shall not for a period of three years be rented, leased, subleased or assigned to any person other than a person for whose benefit recovery of the dwelling unit is permitted pursuant to this subparagraph or to the tenant in occupancy at the time of recovery under the same terms as the original lease; provided, however, that a tenant required to