What is a strong thesis statement about marriage for the short story "Four Summers"?

In “Four Summers,” the author, Joyce Carol Oates, highlights several key ideas about marriage that could be developed into a thesis statement. The short story is told from Sissie’s perspective at four times during her life. In the fourth part of the story, Sissie gives her perspective as a married woman who is nineteen years old and pregnant with her first child. Sissie’s view of marriage appears to be that it is nothing more than a contractual arrangement, an obligation, more or less, as the story takes place in the 1960s, when Americans glamorized the institution of marriage and when women were expected to get married and have children. In the 1960s, for a woman, marriage was considered the road to fulfillment, and Oates challenges that concept in the story.
Sissie is coming of age in the 60s, and though these traditional ideals remained strong, women began to question them during this era of civil rights. Sissie questions the possibility of fulfillment in marriage, and in fact, she questions the sustainability of romantic love. She also questions whether love and marriage are linked, given that she feels confident, based on her experiences, that romantic love is destined to die. Sissie had observed her parents’ marriage and the marriage of her Aunt Sue, and in her eyes, both were filled with anger, unhappiness, and resentment. Speaking from the perspective of a married woman herself, Sissie reveals that she expects these same feelings to surface in her own marriage.