The actor appeared on the ITV1 breakfast show with a beard, confirming that he has changed his appearance to tie in with Ashley's ongoing struggles.
Ashley is left homeless in the coming days as he cannot afford to keep staying at the B&B, while he knows that nobody in the village will want to give him a place to live. His life has taken a dramatic turn for the worse since his abuse of his father Sandy was revealed, and things will deteriorate further for him in the coming weeks.
Middleton, reflecting on the story in his TV interview, commented: "This is a huge change. I've been playing this character for, off and on, 15 years now. So any change like this you embrace as an actor, but I did with some trepidation because I didn't know where it was going to go.
"It really is reinventing the character completely. And they've even reinvented the way the character looks, as you can see, because he's got a considerable downfall to go yet! At the same time, I was very excited. It's a huge story."
Discussing his new look, he continued: "It's great at the moment because I'm not being recognised! I'm blowing that now, aren't I?"
Middleton added that while Ashley's treatment of Sandy was "completely unfair", he has heard from viewers who sympathise with the troubled ex-vicar.
He explained: "I've had quite a surprising amount of feedback from people who understand the pressure upon Ashley, and the pressure of looking after an elderly [person] who's very needy. Sandy isn't as needy as some - I have had people who've had to look after parents with Alzheimer's or things like that.
"The pressure on carers these days - who get very, very little support - is enormous. If there's one message I wanted to get out, it's before you get anywhere near the situation that Ashley finds himself in, where he became violently abusive and there's no excuse for that, you've got to talk to someone. There are agencies out there who are there to help."
Emmerdale airs weeknights on ITV1.