Read and reflect on verse 247 from Surah Al-Baqara: AND IF any of you die and leave wives behind, they bequeath thereby to their widows [the right to] one year's maintenance without their being obliged ...
وَالَّذِينَ يُتَوَفَّوْنَ مِنْكُمْ وَيَذَرُونَ أَزْوَاجًا وَصِيَّةً لِأَزْوَاجِهِمْ مَتَاعًا إِلَى الْحَوْلِ غَيْرَ إِخْرَاجٍ ۚ فَإِنْ خَرَجْنَ فَلَا جُنَاحَ عَلَيْكُمْ فِي مَا فَعَلْنَ فِي أَنْفُسِهِنَّ مِنْ مَعْرُوفٍ ۗ وَاللَّهُ عَزِيزٌ حَكِيمٌ
AND IF any of you die and leave wives behind, they bequeath thereby to their widows [the right to] one year's maintenance without their being obliged to leave [the dead husband's home]. If, however, they leave [of their own accord], there shall be no sin in whatever they may do with themselves in a lawful manner. And God is almighty, wise.