Allison Janney wasn’t expecting to bid farewell to “Mom” so soon.

The 61-year-old said of the show, which premiered in September 2013, ending after eight seasons: “I’m sad.”

Janney, who plays Bonnie, the mother of Christy (played by Anna Faris until she announced her departure last year) said on “The Late Late Show”: “I wish that we’d had at least another year for the writers to have that much time to ramp up to the ending. We sort of found out sooner than we thought we would. We thought, Surely, they’re going to want more ‘Mom’. And they decided not.”

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“There are so many reasons behind that, most of them probably money,” the actress went on. “I know that Chuck Lorre is writing the final episode, and we’re right now filming the third-to-last episode. I’m having a lot of moments where I’m just standing on set, taking it in and looking at all the faces I’ve looked at for eight years.”

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The Oscar winner shared, “It’s going to be very hard to just have it, all of a sudden, it’s gone. And no matter how much I prepare myself for it, I know I’m just going to be tears, buckets of tears. Because it’s been so incredible, all the amazing letters I get from people who are in the program, or people who got sober with us,” referencing her and Christy being recovering addicts.

Janney added, “It’s been a great show to be part of. And it’s so rare when you do something like that, and it affects people in a positive way out in the world. It makes me sad, but onward.”

The “Mom” finale is set to air on May 6.