Even though Landon knows that Jaime will not be able to stay with him forever, he makes a sacrifice by marrying her.
His expectations are for Katherine to marry him for his economic benefits and for her to be loyal to him even though he is not treating her with respect.
His idea was that it is okay to marry a girl even if she is not happy with the relationship.
She does not hide the fact that she is dying from Landon which shows her belief that it is important to be honest in relationships.
Even though it is difficult for her to do this, Jamie requests of Landon, “You have to promise you won’t fall in love with me.” By asking him to promise not to fall in love with her is her way of being honest.
Compared to Petruchio and Katherine, weren't in love when got married. In the end Katherine falls in love with Petruchio and made sacrifices, just as Landon did, but Petruchio’s disregard for her feelings means their love is not genuine.