What is the ruling on taking an interest-based loan for marriage, given financial hardship, numerous family obligations, and the fear of falling into the forbidden?

It is not permissible to take out a usurious loan for marriage. If one has taken out such a loan, sincere repentance is obligatory. If the loan was taken out unknowingly that it was usurious, then it is hoped that there is no sin. It is not necessary to hasten the repayment of the loan if it does not waive the usurious interest, or if there is no ability to hasten the repayment. As for the supplication not being answered, this may be due to the absence of a condition for its acceptance, or the presence of an impediment that prevents it, or that Allah delays the answer for what He deems best. Supplication is never lost; either Allah answers it promptly, or saves it for the supplicant, or diverts evil from him through it. It is advised to be patient, renew repentance, persist in good deeds, and seek refuge in Allah Almighty.