Just typed in Mary Ellen without a surname, Waverton 1865.
it comes up with a Mary Ellen Shone b.Waverton Cheshire.
It gave her age as 6,so in 1911 on your Census she is aged
46,and her husband as Edward as a cowman, in a earlier census he has a simular job,it could be the one he married,
but so far I too cannot find a marriage for them,I hope
this goes some way to solve your problem.

Regards, Charles.