He has feelings for her and she has feelings for him, but what's stopping him is the fact that he feels he's too old for her.

Thanks :)

They're one of the two secondary couples, not the main couple, but Love in Between has an example of this - they both love each other, but he holds himself back because he feels he's too old for her. Ultimately they do end up together and get a happy ending, though.

Hidden love. New Chinese drama the girl feels more like she is too young but he also has this issue as well