In my own humble oppinion , this decision shouldn;t be taken lightly . It is quite an important matter from my point of view .

The guy is not smart nor dumb nor selfish nor kind. He's just being direct and realistic in the matter of pursuing his own career and i think the bf is a lovely man. He asked his gf if she would go over and be together with him. It is not a question of marry or not to marry but at least he asked. Then there was another curiosity , the guy directly tell the girl , 'well if you do not plan to come over then i think it is better to end the relationship (for the best of our career advancement)

My point is there are many perspective to look into this matter but we will have to go to the basic again , the girl will have to think of herself (like consider the consequences if she goes over to be with her bf) It is just to clear the doubts on herself so that she could make a clearer decision.

There are also other option for the girl in this matter, if the guy do not mind. Ask about the involvement of the girl future in his future. Is she part of his plan? (i think this is very important) If the girl is part of his plan .. then i don;t see why she must break up with that guy. But if it's not then i think you must sit down and think harder.

I don;t see a fault if you decide not to go over . I think it's alright because you're still you and there's probably some other reason ( not just couldn't cope in different environment). It is important to search the hidden reasons so you'd be clearer on the doubts she's having now.

my point is clear the doubts and then re-consider on the consequences and you'd have a clearer mind to decide .

There's not good or better choice okay...it just how long more do you want to think of this. Limit your time and decide firmly.

If you can take something from someone you also must learn to let go if it's too heavy.

i hope i helped and that it's enlightening for your friend.
Find what is inside herself and not what other people say (they will continue blabing about it.

Regards,
Alan Tan