Washington Willis and Emily Horn Get Married

Today I found an transcription of marriage records for De Soto Parish 1837-1860. Washington and Emily were listed as married on 28 May 1856. I don't have the cash to send for original copies so I have to make do with what I can find on the internet.
The rest of the day I spent slogging through censuses and whatever online records I could find.
I can't imagine what happened to Martha. Here's the breakdown

• 1850 Martha J. Willis on census in Alabama with family (William Franklin and Ann J. Stanley Willis)
• 1854 James Welch (bn 1830 Ireland) and Martha J Willis marry in Franklin County, Alabama
• 1860 James Welch in on census Shelby county Texas with Nancy (?) and  4 children. None of them Fannie.
• 1860 Martha's parents and some of her siblings in Bethany, Panola county, TX
• 1880 Martha's daughter, Eliza Jane Welch is living with her half-sister Fannie Welch Myers in Nacogdoches.

Where did Martha go? And where did Eliza Jane come from?

We have several records with Eliza Jane's date of birth as 1858, 1860 and 1861. We also have her place of birth as Joaquin, Texas and Logansport, Louisiana.