Because all we can do with such limited info is to take her word for it. Of course, you are correct that it could be just that she is selfish and is the real problem here, but we would hav eno way of knowing htat.
True. We don't. But the most severe complaint she comes up with is that her husband is "unkind". Doesn't sound to me like the marriage is irrecoverable to me, even it the charge has any truth. It does seem to me that conservatives should be trying to find ways to resolve this instead of condemning yet another child to fatherlessness.
I would also say that, if she is determined to break up her family, she could at least have the decency to stay in Sweden where Dad and daughter can be together.