Responses

he surely thought it was much better for her to suffer for a few years after he left than to have her tied down to caring for him for many, many more years and not letting her fulfill her dreams. that's why he was so happy to see that she got the job she wanted. he wasn't sure what was going to happen, and he chose what he thought would hurt her. this is the typical behavior and way of thinking from people who suffer from cancer.
i'm glad ho knows him and ahjussi can talk instead of choosing to hide important stuff from each other! i know it's for the plot, but it's still kinda iffy how grandpa wanted to avoid someone else's supposed suffering, but didn't think that leaving without a word would be hurtful to the one he left behind.