The woman's "boyfriend" in my view was a total A-hole about this situation.
IF he had discussed the matter with her beforehand in recognition of the fact that the property was HERS it might have been different. Ditto if it had been THEIRS. If theirs, then she had veto rights. Since it was HERS, she is the only person with rights to accept or exclude.
I am glad she finally kicked him out. Personally, I would have kicked him out the moment he became so intransigent and disrespectful of what was her obvious right to make decisions about her own property.
Typical macho macho man as far as I am concerned and therefore not worthy of a second thought. (Notice: not all men are macho macho, but this guy definitely was, and therefore his opinion of her actions is irrelevant.)
As for his family's reaction: clearly the rotten apple has fallen not far from the tree.
Apparently being a-holes runs in the family.