If the stated is true , then the girl is lucky that marriage was called off. You wouldn't want to be with a partner who is jealous or unhappy because their partner is earning more than them. After a certain time, insecurity would creep up and rather than having mutual conversation, it would create more misunderstandings from boy's part. Totally absurd from boy's end as well, if this is the reason to break up from marriage.
But if the situation would be something else, and something is missing from the mentioned story here, then cannot say anything for sure.