I honestly thing the author is awesome. she wrote a story that managed to link events, feelings, thoughts and actions of all characters up so well.
XY want a peaceful life and she love a companion and hate the lonely and abandoned feeling (she can talk the monkey into wanting to slam himself onto the wall because she want to have company). She loves CX as a brother who is her only companion when they are young. so her choices and actions are revolving around these two priorities.
It is very important for a woman to know what she wants and what she needs. It is only after you know what u want and need, you are able to choose the right one. when we say the Mr Right it is never he is PERFECT but he is the just the right one for you. TSJ is not perfect. he is soft hearted and way too kind and not decisive enough but it is precisely that soft heartedness that create a man who loves and cares for XY thoroughly and put her no 1 at all time. in fact put her above himself. EVen though his action of unable to break the engagement and taking too much consideration to his grandma and clans makes him look useless and weak and seemingly not putting XY first. But we have to understand that he is working on it. he never choose others over XY. all that he is doing since his return to home is doing his best to return to XY as YSQ but his characters make him need to do it slowly by considering everyone. his choice has always been clear. XY!!!! he is permanently on the journey of going back to her.
if he is a cruel man and can leave his family or kill his own family, i don think he will be the right one for her. it is always a package. the author showed his imperfections but he is what XY wants and need. Basically we cannot choose a man we like and make him changed. FL was so right in explaining to his sister. you want CX you will never be the only one. you want to be the only one in a man's life you cannot want CX.
TSJ is so intelligent and he can strategise to get CX the world/throne for XY sake because he understand only with CX in power, then XY will be worryfree. otherwise she will be forever worrying about CX. the surprising reward is in the end CX in power will make sure XY is safe and away from harm because she has the no 1 man in the kingdom to love and protect her. that loop is closed too.
XL has a element of arrive too late and do too many nasty things in the beginning. But that is life. i think the author has shown us that we cant turn back the clock. He also has his priorities. And again even though he loves XY deeply, but in the end he will still want to die on the battlefield. Sometimes we called this it is not meant too be.