The same is true of marriage. Problems are inevitable, and it would be naive for a couple who are contemplating wedlock to expect a life of bliss.
فَقَدْ يَكُونُ ٱلطَّقْسُ قَاسِيًا ،‏ مِمَّا يَضْطَرُّكَ إِلَى ٱلتَّمَهُّلِ وَٱلْقِيَادَةِ بِحَذَرٍ .‏