“We have been living together for more than 3 years, but we filed our tax separately while filing "Single". (He does not have any income, so I don't really worry about the tax.)”
This inferring leads to one that they ARE in a commonlaw relationship. The only reason she didn’t fess up to changing their relationship status with the Government was the bf had nil income .
They were commonlaw
That ship has already sailed; the misrepresentation occurred with the OP's own PR application.
You both are most likely right. Which, again, I acknowledged in my very first post. However, I proposed to the OP to seek a legal advise. Since I have at least one known record where exact same (your) arguments didn't hold and PFL was successfully addressed, precisely based on the weak definition of conjugal relationship. I see no reason of such hostile reaction though.... perhaps you both have a law degree or read a lot of court cases on that matter, if so I humbly retreat.