It most assuredly screws everyone equally. Vengeful cohabiting partners, current or ex-, can make an allegation that police and prosecutors, by virtue of having received TONS of federal grants to beef up their training, equipment and prosecution of alleged domestic violence cases, take up and prosecute to the hilt, per the terms of their grant funding, facts or self defense claims notwithstanding.
Even if the case gets pled out to something else - like disturbing the peace - the feds interpret the ultimate conviction as having arisen from domestic violence, and accordingly treat the "disturbers of the peace" as being included under the prohibition, and will deny them on NICS background checks and have them federally prosecuted if found in possession of a firearm.
Not only the vile, violent wife-beaters get caught up in this mess - the "victim" can be only pushed, held back, or simply placed in fear of their "partner" or ex partner might touch them against their will, and charges flow.
This Lautenberg stuff is one of the Brady's first, strongest and longest-lasting successes. While I don't condone violence in any form, this law went way too far IMHO, and needs to be seriously reined in.