Don't have a documented proof, i.e., marriage license, but Rachel is listed as Rachel Newberry in the 1850 Jackson Co AL census -
1850 Jackson Co AL - District 21 1403403 NewberryRachel77FVaX REMARKS:Handwritten page No. 265. 2403403 McElyeaJames G.37MnoneTennXX REMARKS:"Idiot" 3403403 OliverJames28MLabourerTenn 4403403 OliverTalitha25FAlaX 5403403 OliverEliza J.5FAla 6403403 OliverElmira4/12 FAla REMARKS:Two females age 4/12 in household. 7403403 OliverSamira4/12 FAla REMARKS:Two females age 4/12 in household.
I know this doesn't help but at least we know she did remarry.