Past cannot be changed, they already happened, what's important is what you do and can you do NOW.
Ludia/Lydia was given a chance to relive her life. Her past and other timeline has already happened and will never change. What's important is her PRESENT ACTIVELY FIGHTING TENDENCIES and doing what's best for Rica. Even when she thinks she's about to do something she thinks is right, she pauses and analyzes over and over if that's what she should really be doing, if that was indeed for Rica or for herself. Not everyone can be selfless but it is free and should be appreciated when they try to be one because it's NOT damn easy.
Knowing her past is not for her actions to be excused. It's called giving context and weighing in whether the reason and reaction match in weight. I'd say yeah, it checks out. Is it justified? Is it right? No, and the character recognizes that herself. Self-reflection and accountability is ALSO DAMN HARD TO DO and must be appreciated when one does it.
Idk why other people (fiction or irl) think they have this opinion of "forgiving" (or not) for the people who were done wrong. It's no one's place to do the forgiving but the actual person who was wronged. Rica ALWAYS chooses to forgive, even when she didn't have to, she chooses to abstain giving anything - A LOT OF PEOPLE SHOULD LEARN FROM THIS CHARACTER.