menda tshering:
He doesn't give anything up. He helped XL for 30 years feeding his soldiers and horses without CX 's knowledge. Why do you think XL takes away the bride on her wedding day? He ofcourse wants to pay jing back and also thinks he's the best choice for XY. As for jing being completely in love with XY is the reason she chooses him. She knows deep in her heart he'll never let go.
XL and TSJ did business together for hundreds of years before TSJ disappeared and later became YSQ. That relationship was transactional. XL had no debt to TSJ that he needed to repay.
XL takes XY away on the day of her wedding with FL because TSJ buys his promise from him. TSJ agrees to give XL 37 years worth of provisions for his army in exchange for XL invoking the promise that XY made him (to do one thing that he asked of her, immediately when asked, in exchange for XL accepting the transfer of the poisonous bug from CX to him) in order to get her to leave the wedding and run away with him.
XL's long-term plan also included making sure that XY had a person who she could rely on for her whole life. His actions show that he did not believe that FL could be that person, and he did believe that TSJ could be that person.