Green’s Dictionary of Slang

(US teen) to disassociate oneself from someone after a disagreement or an unpleasant occurrence; also as adj., estranged.

2002		mkrann ‘We Boyz’ on Nifty Erotic Stories Archive 🌐 I could have clearly stated none of your business, but that would mean that I was definitely hiding something. If I told him the reason...there was the chance that me and Terry would become unbenefit.
2008		posting to www.space.com 12 Dec. 🌐 You chose to unbenefit! I’m just telling you what’s my truth. Your truth is what you can believe, but I know you’re being deceived.