Need help with tearing down a brick wall ive had for years..

Unfortunately, I have that usual problem of Common surnames. I had a 4x Great Grandmother named Clarissa "Tillsie" Brown (1795-aft.1870) wife of my 4x Great Grandfather, Anderson Windsor (1810-1886). Clarissa claims to be from North Carolina. She married Anderson on February 12th, 1826 in Richmond County, Georgia. They stayed in Richmond County in 1830 and 1840 then moved to Forsyth County, GA in 1850. The rest of her life she lived in Gwinnett County, Georgia where she died.

This might be a stretch and difficult since the last name Brown in North Carolina is next to impossible to find if I dont have a particular area she was from. I have no idea who her parents are. I even checked to see if any Browns were on the marriage certificate but can't find any.

My next guess is that she was a widow and Brown isn't her real last name.