Anata no Ai nado Irimasen

Knowing she'd be little more than a wife in name only, Rachel still married the Commander of the Kingdom's Order of Knights, the man she had long loved from afar. After a loveless marriage and at long last being blessed with a son, she pours everything into raising him, only to lose her life in the wake of a certain incident. But when she opens her eyes, time has turned back to her wedding day! Why has she been given a second chance at life, and what is the meaning of starting over? This time, to protect the child she truly should have treasured most, the beloved son she loves with all her heart, the great reversal story of an oppressed noble lady begins!!

(Source: AlphaPolis)