Adrian, I have no answer to your dillema, just empathy!
My Edmonds line goes back to early 1700's and ends in exactly the same way.
The last confirmed event we have is the marriage of James Edmonds to Sarah Ead in 1713.
After extensive searching, the most likely candidate for this James is a christening in a neighbouring parish. The entry in the parish register is in LAtin (!) and the translation we have managed to get reads as follows:
"James, son of MAry Edmonds and (as claimed by MAry) of Ralph Edmonds, her former husband, who went away on the day of the annuciation of the Virgin Mary in 1676 and who she declared to be dead two years ago, and is now rumoured to come and go furtivley among the other women, invisible to all but his wife.
Putative son of John Tavernor."
My reading of this is that Ralph deserted Mary. She told everyone he was dead. she had a fling with John Tavenor and got pregnant, but rather than admit having an affair she tries to con everyone that hubby has been making secret visits!
What do you think?
But - if John TAvenor is the Dad, it brings my Edmonds line to an end. Or should I follow RAlph to carry on the Edmonds line - that doesnt seem right as James if James was not his son!
I hope in your case, that you find that that there are two Elizabeth Hemes, and so you can continue your line!