You said marriage is not obligated but we're told it's half of the deen
The “half our dīn” saying comes from a group of hadith narrations all of which are of questionable authenticity. One of them comes from al-Bayhaqī’s collection and the chain of narrators includes Yazīd al-Raqāshī, who is untrustworthy according to al-Tirmidhī and Ibn Ḥajar. Another version comes from al-Ḥakām’s collection, and the chain contains ʿAbd al-Raḥmān bin Yazīd, who is also untrustworthy according hadith scholars.
There is another famous saying that says “A woman completes part of a man’s faith”, this is not from the Prophet, but from Ṭawūs ibn Kaysān, it is just a scholar speaking his personal opinion.
The hadith scholar al-Albānī performed a detailed study of these narrations and considers all of the them untrustworthy except one that says “A woman supports a man in part of his dīn, so let him worry about the second part.” This hadith is not authentic due to its chain containing at least one person whose is known to be of arbitrary reliability (he sometimes speaks the truth, sometimes says something completely wrong). Al-Albānī concludes that the hadith has a status of ḥasan, meaning that it is not authentic (ṣaḥīḥ), but that its meaning sounds good and one cannot say with certainty that it is fabricated.
In conclusion, therefore, this “half our dīn” concept is not firmly established and cannot be used as a basis for deriving principles.