I don't think Xiaojing falls for Jim just because he is successful, athough it helps. Her marriage with Wei is somewhat broken first, mostly because Wei gave up on himself.
There are plenty of successful people who are neither likable nor worthy to be loved. I believe Xiaojing and Jim are somehow connected emotionally and feel the attraction physically. Whether it can be called "love", it is just a term.
If liking someone of the opposite gender in mind is the same as affairs, I guess very few people in this world can claim themselves as "pure" :-). Xiaojing only really pursued her new "love" after she ended the marriage with Wei. I think that's respectful.