What is it that prevents me from committing to prayer and abandoning sins, despite my awareness of their حرمة (prohibition/sacred inviolability), and how can I overcome the increasing desires after numerous attempts to commit?

You have not given the quest for uprightness its due. For whoever strives earnestly and sincerely for Allah, His divine enabling grace will not fail him. Be truthful with Allah and strive against your own self with sincerity, and trust that divine enabling grace is close to you. Strive diligently in supplicating for guidance, accompany righteous people, and avoid the companionship of evil people. Increase your reflection on death and the Day of Reckoning, and know that abandoning prayer is among the greatest sins.