Is marriage an eternal destiny or a conditional destiny?

It is obligatory to believe that everything is by divine decree (qada) and destiny (qadar). Destiny is a secret of Allah among His creation, and one should not delve into it. A Muslim must strive and take lawful means, including supplication (du'a). Destiny is of two types: an unalterable decree (qada mubram), which is eternal and does not change, and a contingent decree (qada mu'allaq), which is recorded in the scriptures of the angels and changes through supplication, charity (sadaqa), and righteousness (birr). This contingent decree is what is referred to in the verse: "Allah erases what He wills or confirms [what He wills], and with Him is the Mother of the Book" (Quran 13:39), and in the hadith: "Nothing repels divine decree except supplication, and nothing increases one's lifespan except righteousness." The alteration of individual records does not contradict Allah's eternal knowledge.