The "boyfriend loophole" is a made up term for political consumption, covering something the existing laws do not, and some people think should.
Right or wrong existing law covers a domestic violence CONVICTION making someone a prohibited person (essentially for life) unable to possess firearms.
The "loophole" is that existing laws have limits (and MUST have defined limits in order to be fairly applied) and those defined limits about who is, and is not a "domestic partner" were not broad enough to make some people happy.
It's NOT a loophole, but they call it one for the emotional reaction the word carries. What they call a loophole, other people call following the law.
We now have a new Federal law that expands the scope of who will be considered a "domestic partner" under the law, and typically the new standards and limits are extremely vague. I suppose one shouldn't expect better from a law that was crafted, "debated" and signed into law in a MONTH.....
we've already seen a case where the previous law was stretched to the unbelievable in order to try and punish someone. A woman who's son was shot by a cop actually filed suit to have his right to arms taken away (so he couldn't be a cop anymore) under the DV laws, claiming that they "had a child in common", in order to qualify under the DV law limits about who has and doesn't have standing.
The case was eventually shot down because the only thing they had as a "child in common" was that the guy shot was her child and the cop shot him.
The woman did eventually face perjury charges, no idea how that went because after that, it was out of the news.
Point here is, with people trying to stretch existing law to that extreme, what might we get with the new law, and its much broader and ill defined scope?
Not much good, that I can see...and an absolutely horrendous potential for abuse...