Can I be helped to return to prayer and reading the Holy Qur’an after a period of discontinuation, and to remove the barrier of unhappiness that prevents me from achieving khushu (devotional humility)?

If the worshipper is cut off from obedience due to sins, he feels a sense of desolation in his chest, and this is an indication of the life of his heart. To remove this desolation, one should increase repentance and seeking forgiveness, observe obligatory prayers and supererogatory acts, keep company with righteous women, lower the gaze, and avoid places of temptation.