For Marriage
It will lead you to Sin and Haram. Strictly avoid it and put your Tawakkul in Allah.
For Business / Deal
There is a vast difference between healthy trade and Riba (usury). Do not deceive yourself.
الَّذِينَ يَأْكُلُونَ الرِّبَا لَا يَقُومُونَ إِلَّا كَمَا يَقُومُ الَّذِي يَتَخَبَّطُهُ الشَّيْطَانُ مِنَ الْمَسِّ ۚ ذَٰلِكَ بِأَنَّهُمْ قَالُوا إِنَّمَا الْبَيْعُ مِثْلُ الرِّبَا ۗ وَأَحَلَّ اللَّهُ الْبَيْعَ وَحَرَّمَ الرِّبَا ۚ فَمَن جَاءَهُ مَوْعِظَةٌ مِّن رَّبِّهِ فَانتَهَىٰ فَلَهُ مَا سَلَفَ وَأَمْرُهُ إِلَى اللَّهِ ۖ وَمَنْ عَادَ فَأُولَٰئِكَ أَصْحَابُ النَّارِ ۖ هُمْ فِيهَا خَالِدُونَ
Allatheena yakuloona alrriba la yaqoomoona illa kama yaqoomu allathee yatakhabbatuhu alshshaytanu mina almassi thalika biannahum qaloo innama albayAAu mithlu alrriba waahalla Allahu albayAAa waharrama alrriba faman jaahu mawAAithatun min rabbihi faintaha falahu ma salafa waamruhu ila Allahi waman AAada faolaika ashabu alnnari hum feeha khalidoona
Those who devour usury will not stand except as stand one whom the Evil one by his touch Hath driven to madness. That is because they say: "Trade is like usury," but Allah hath permitted trade and forbidden usury. Those who after receiving direction from their Lord, desist, shall be pardoned for the past; their case is for Allah (to judge); but those who repeat (The offence) are companions of the Fire: They will abide therein (for ever).