כִּֽי־כְאִשָּׁ֧ה עֲזוּבָ֛ה וַעֲצ֥וּבַת ר֖וּחַ קְרָאָ֣ךְ יְהוָ֑ה וְאֵ֧שֶׁת נְעוּרִ֛ים כִּ֥י תִמָּאֵ֖ס אָמַ֥ר אֱלֹהָֽיִךְ׃
For the LORD hath called thee As a wife forsaken and grieved in spirit; And a wife of youth, can she be rejected? Saith thy God.
Read Jewish philosophy on Isaiah 54:6: Rambam's Guide for the Perplexed, Saadia Gaon, and classical Jewish philosophical sources, free online.