90 Day's Brandan Is on the Phone 24/7 with 'Insecure' Girlfriend (Exclusive)

The '90 Day Fiancé' couple were scarred by cheating exes, and now Brandan gets physically "tense" around women because of Mary, who dissolves in tears over not being called his "first love"

Brandan and Mary are bringing a different type of romance to 90 Day Fiancé: The Other Way.

In PEOPLE's exclusive sneak peek at the season 5 premiere, the couple's jealousy and trust issues flare up during a routine teeth cleaning as Mary keeps a watchful eye (via FaceTime) over Brandan's interactions with a female dental assistant.

As viewers see Brandan heading into the appointment, he explains in a confessional interview that "Mary wants to know what I'm doing, and she's very clingy, and I really like that because I'm kind of the same way."

He shares, "We have very similar past histories. Our exes cheated on us, and it contributes to our jealousy and insecurity issues. So being on the phone 24/7 helps give that reassurance that we're not doing anything that we shouldn't be."

TLC

Brandan arrives at the doctor's office and asks the dental assistant if his phone can be placed somewhere Mary can see the consultation.

After dating Mary long distance for more than two years, Brandan admits in a confessional that he has begun to "get anxious and tense up when I'm around other women now because I don't want to fight with Mary."

When the dental assistant innocently makes small talk, asking Brandan if Mary is his first love, he responds, "No, it's not."

After the dental assistant steps out of the room, Mary tears up and confronts Brandan: "You lied to me. You said I'm your first love, but now you said I'm not."

Brandan attempts to fix the situation by telling Mary that he said that because she is not his first girlfriend, but Mary gets even more distraught and reminds him that she also has an ex.

"You just said no," she says forlornly.

TLC

The 23-year-olds are one of the newest couples — not to mention the youngest pair — on the latest season of TLC's 90 Day Fiancé spinoff, The Other Way.

"Brandan and Mary spend every waking (and sleeping) hour on video call with each other," according to a TLC release. "This obsessive and possessive behavior has led their friends and families to oppose the relationship, but not being together is no longer an option for these two."

Though the pair have never met in person, they've "made extraordinary sacrifices to prove their love to one another, and Brandan has invested everything he has into building a home for them in the Philippines. There's no turning back and no backup plan, but Brandan is in for a rude awakening before his plane has even left the ground."

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90 Day Fiancé: The Other Way premieres Monday at 8 p.m. ET on TLC.