Is the Istikhara prayer prescribed concerning marriage, in the presence of fears and health problems (especially psychological ones) that may affect the performance of marital rights, despite the obligation of marriage?

The permissibility of performing Istikhara concerning the fundamental principle of marriage depends on knowing its ruling for your specific case. Istikhara is not performed for actions that are fundamentally obligatory or recommended (mustahabb); rather, it is permissible for choosing among them or prioritizing them. The ruling on marriage varies according to the circumstances of individuals. Istikhara is not a means to discern Islamic legal rulings unless a person has exerted their utmost effort to understand the Shar'i ruling and has not been able to definitively ascertain the correct opinion. It is advisable to proceed with marriage if someone whose religiosity and character are pleasing comes forward, and not to let unseen matters be an impediment.