"I was feeling love toward Lauren, but I could not exactly tell you why," Arie wrote in his People blog.
During Monday night's The Bachelor episode, Arie visited Lauren's hometown of Virginia Beach, VA, where he met her family and got to spend more time with the blonde beauty.
Up until this point, Arie and Lauren's relationship has been a slow burn, with Lauren taking her time to open up, be vulnerable and share stories about herself and her past.
Arie has put a lot of effort into pulling Lauren out of her shell, but many viewers have questioned why he's so determined given other bachelorettes are shown falling in love with him and having no problem expressing themselves.
"I was so excited to see Lauren... As soon as I saw Lauren on that beach, all of my fears and anxieties melted away," Arie wrote of Lauren's hometown date.
"Last time I saw her, we said we were falling in love with each other. This was heartening but also surprising. I still didn't quite know where these feelings were coming from."
Arie and Lauren's romance appears to lack depth, but the couple has some type of magnetic pull to each other. Arie, for instance, once told the cameras he felt drawn to Lauren since the start of the process.
"Even if I couldn't tell you why, my feelings were real and I wanted to try and enjoy them," explained Arie, who has been criticized for just being attracted to Lauren's stunning looks.
For the day portion of their date, Arie and Lauren rose horses on the beach, and he said they had a "great" time "deepening" their connection.
"But meeting her family definitely loomed over my head. All I knew was that her dad was a military man and that I should expect him to be very tough. The last guy they met was her former fiance and they were going to be very hard on any new man in Lauren's life," Arie wrote in his blog.
Lauren was previously engaged to pro hockey player Christopher Crane and they were set to marry in July 2017, but their relationship ended in 2016.
ABC executive Robert Mills revealed during an appearance on The Ringer's Bachelor Party podcast last week that Lauren had been engaged, not once, but twice before her stint on The Bachelor! It's unclear, however, what happened with her first engagement.
"My time with Lauren's family started exactly how I imagined. The tension was high and the silences were long. At the time, it felt awkward and nerve-racking (especially given how much I cared about Lauren), but now I realize it was all coming from a place of love," Arie continued in his blog.
"They were worried about this strange man entering Lauren's life and felt it was their job to be her protector."
Arie admitted he thought time with Lauren's father was going to be "the hardest" part of the night, but her mother and aunt were "way harder" on him.
"When I asked her mom if she'd give her blessing on an engagement, she eventually said she'd trust Lauren in whatever decision she were to make, but did not give her blessing easily," Arie said.