Question

Hello Rabbi Michi! 
Erev Rosh Chodesh Sivan is totally awesome! 
Yesterday a friend called me and told me that he took Tractate Berakhot with him on his trip abroad, and he asked me a question he had. Since these are aggadic passages, I didn’t bother looking at them when I studied Tractate Berakhot (my view on aggadah is like yours; even in Tractate Megillah I read quickly and skip).
The Talmud in Berakhot (31b) continues discussing Hannah’s prayer:
“If You will indeed look—Rabbi Elazar said: Hannah said before the Holy One, blessed be He: Master of the Universe, if You will indeed look, good; and if not, You will look. I will go and seclude myself before Elkanah my husband, and since I will seclude myself they will make me drink the sotah waters, and You cannot render Your Torah false, as it is said (Numbers 5:28), ‘And she shall be cleared and shall conceive seed.’ This works out well according to the one who says that if she was barren, she is remembered with children. Fine. But according to the one who says: if she used to give birth painfully, she will give birth easily; if she used to bear females, she will bear males; if she used to bear dark children, she will bear fair ones; if she used to bear short children, she will bear tall ones—what can be said? For it was taught: ‘And she shall be cleared and shall conceive seed’ teaches that if she was barren, she is remembered with children—these are the words of Rabbi Ishmael. Rabbi Akiva said to him: If so, then all barren women will go and seclude themselves, and this one, who did not act improperly, is remembered with children? Rather, it teaches that if she used to give birth painfully, she will give birth easily; if short, she will bear tall; if dark, she will bear fair; if she bore one, she will bear two. What then is the meaning of ‘if You will indeed look’? The Torah speaks in human language.” (Sorry for the copy-paste, like wow.)
Seemingly, the Talmud here is giving permission to a sotah to commit adultery so that she can undergo the test of the bitter waters. How does that make sense? What the Sages are doing here feels very strange to me.
If you have an answer, thank you very much.
Tell me if you didn’t understand the question.
Thanks🙂