Hi - This was a tough one! To make a long story short, I think I found your grandmother and her second husband, EDWIN R HINKS.
On the website, "findagrave.com" is ELIZABETH N HINKS, died May 1964 (buried May 12, 1964) - her "memorial" number is 27417423. She and EDWIN R HINKS are buried in the IVEY HILL CEMETERY in Alexandria City, Virginia. (ELIZABETH is in Section N, Lot 149, Site 2; EDWIN is in Section N, Lot 149, Site 3).
If you are not familiar with this website, just go to www.findagrave.com and "click" on "search 96 million graves", then just type in her "memorial" number!
I have her social security number, but really don't want to post it here. Please send me a private message so that I can give it to you. You can request a copy of her Social Security Card Application, which should help you find out more about her.
The social security death index has "ELIZABETH N HINKS, born April 8, 1898 and died May 1964 "(social security card issued in Maryland).
Since you know when and where she died, perhaps you could obtain a copy of her obituary in the newspaper.
Do you know the names of ELIZABETH's parents? If I had their names I might have better luck finding ELIZABETH on the 1900, 1910, & 1920 Census's.
Hope this is what you were looking for! Sincerely, Melinda