Zach Shallcross has a decision to make, whether he likes it or not.

The 26-year-old's quest for true love on The Bachelor is nearing its end—but that doesn't mean he knows where his heart is leading him. As E! News' exclusive sneak peek at the season 27 finale reveals, Zach is feeling less confident than ever over which of his finalists—Kaity Biggar or Gabi Elnicki—will be his fiancée. However, the same can't be said for the women.

"For Zach and I, it's been a very natural progression," Gabi says in the preview of the March 27 episode. "He gets me, and I think I get him. I do definitely have a lot of confidence in what a life could look like between the two of us."

That is, until Zach starts to open up to her on the beach in Thailand.

"I'm nervous, to be completely honest," he admits. "I know this is not what you want to hear, but I'm so torn. It's the biggest decision of my life and I don't know full where I'm going to be in two days. But I feel so good that the right thing is gonna happen."

The update hits Gabi particularly hard, considering she has been open about feeling like second pick her whole life.

"I'm starting to really get in my head," she says through tears in a confessional. "I was doing just fine until he was like, 'I have a very tough decision to make.' Well, make the f---ing decision."

The indecision comes after a chaotic Fantasy Suites week where Zach broke his own no-sex policy and ended up saying goodbye to Ariel Frenkel.

And hearing Zach struggle to choose frustrates Gabi, who tells the camera, "I'm sick of self-doubt, I'm sick of feeling like I don't know if I'm enough. I just think that if Zach knew how he felt about me, he'd say it."

At least there's always Paradise...

See who gets Zach Shallcross' final rose in The Bachelor season finale, Monday, March 27 at 8 p.m. EST on ABC.