Neal McDonough says he “lost everything” after being blacklisted from Hollywood — all because he refused to kiss another woman on screen!

The “Yellowstone” actor discussed the low point in his life in the exclusive preview clip of Wednesday’s “Nothing Left Unsaid” podcast obtained by TMZ … and he says not only did he lose material things, he lost his confidence as well.

Neil tells hosts Tim Green and Troy Green his work ran dry for about 2 years because Hollywood wouldn’t accept his boundary … and the deep plunge in his career took him on a “tailspin.”

He says he took up drinking and lost his identity before his wife, Ruve McDonough, helped him find his way out of the dumps. In the preview clip, he doesn’t specify when he went through his rough times.

Times have changed … and he even released a new project in May — “The Last Rodeo” —  that sees him kissing a woman onscreen. How did he move past the hurdle? His real-life partner jumped in to play his wife!

Neal further discusses this dark chapter in his career, Clint Eastwood changing his life, playing so many villains over the years and more on “Nothing Left Unsaid” — which drops Wednesday morning.