Canto 2 -
Ayodhyā-kāṇḍa
Chapter 118: Conversation Between Sītā and Anasūyā
Text 2.118.3

यद्यप्येष भवेद्भर्ता ममार्ये वृत्तवर्जितः।
अद्वैधमुपचर्तव्यस्तथाप्येष मया भवेत्॥

yady apy eṣa bhaved bhartā mamārye vṛtta-varjitaḥ
advaidham upacartavyas tathāpy eṣa mayā bhavet

yadi api = even if; eṣaḥ bhavet bhartā = husband is; mama = my; ārye = noble lady; vṛtta-varjitaḥ = devoid of good conduct; advaidham = without hesitation; upacartavyaḥ = serve; tathā api = still; eṣaḥ = Him; mayā bhavet = I should.

Noble lady, even if my husband is devoid of good conduct, I should still serve Him without hesitation.

Advaidham upacartavyaḥ (“should serve without hesitation”) indicates that such a husband should be fully served without distinguishing between a husband with good qualities and a husband without good qualities.1

1 Nevertheless, she should personally ensure that she does not engage in any sinful activity or endorse the sinful activities of anyone including her husband. In his comment to Śrīmad-Bhāgavatam 7.11.28, Prabhupāda has pointed out that a woman who has given up the association of a husband addicted to sinful activities should not remarry [and, by implication, should not develop an illicit relationship with anyone]. Women interested in following Vedic dharma should carefully consider all of these instructions with maturity.