Gordon Beurskens was found guilty of siphoning £77,580 from five different bank accounts belonging to Jimmy and Nettie McQue.
The former independent West Lothian councillor, who had known the couple for a decade, claimed it was a loan he was paying back with interest.
But last week he was found guilty by a jury at Livingston Sheriff Court following a three-week trial.
Now the 51-year-old has spoken of his fears about being sent to prison, and claimed his conviction was "politically motivated".
Mr Beurskens said a political rival had previously appeared in the public gallery to "gloat" at his downfall and said he was "genuinely shocked" when the jury returned its guilty verdict.
He said: "I expected this would be the end the end of a five-and-a-half year nightmare.
"It would seem the second instalment of that nightmare is yet to begin.
"It's stomach churning to think that having gone through what we have it is still to reach a conclusion.
"It feels like you've been kicked in the stomach. The damage to my reputation is incalculable.
"The prospect of jail is frightening. I would just have to cope but I would be going to jail an innocent man."
Beurskens held a third- party mandate over the McQues' financial accounts and Mrs McQue, 86, told police she trusted him so much she would "sign anything" he put in front of her.