Things are getting serious!

Peter Kraus is definitely a fan favorite to walk away with Rachel Lindsay's final rose — and on their last one-on-one date on tonight's episode of The Bachelorette, the personal trainer opened up about his last relationship.

In an emotional conversation, Peter, 31, revealed he blamed himself when it came to his breakup with his ex-girlfriend and teared up explaining what went wrong to Rachel, 31.

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"I saw tears streaming down her face, and I blame myself for that," Peter told Rachel of his ex. He also shared his fears surrounding a future proposal.

"I hope to be ready to give my heart up to someone else," he explained. "I can only say that I think that I am so if I get to the end of this with you and I do get down on a knee and propose and we're engaged, I want it to be because that's 100 percent where my heart is at, at that time.

Rachel went on to ask if he didn't feel that way at the end of the journey, would he not propose.

"If I am having reservations, and we're getting that far into it, then I will let you know," he cryptically added.

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So who is Peter's ex-girlfriend that brought on his emotional confession?

Meet Brittany Hansen, the brunette beauty who is rumored to have had Peter's heart before he was cast on the ABC series.

"My knight in shining Armani," she captioned a photo kissing Peter in an Instagram photo from 2014. In another photo, the photogenic couple rang in the new year together.

Along with her beauty, the Wisconsin native also has brains, working as the premise manager at Red Bull and graduating from Bethel University, according to her LinkedIn page.

Her other passions include fitness, fashion, flights, and festivals. Obviously, Peter has great taste in women.

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