"Unexpected" star Matthew Blevins wants to have his cake and eat it too -- or in this case -- ditch his girlfriend, Hailey Tomlinson, for her best friend, Hailey Tilford.

In an exclusive sneak peek of Sunday's upcoming episode, Tilford reveals that Matthew has been reaching out to her in a "different" way.

"Recently, Matthew has been.. talking to me like a little different than he usually does," she says. "He's been texting me late at night and telling me not to tell Hailey, and I don't feel like that's right."

Hoping for answers, Tomlinson decides to give her boyfriend a call while Tilford simultaneously sends a Snapchat to Matthew and -- here's the shady part -- he doesn't answer the phone call, but he opens the Snapchat--meaning his phone was out and he most likely purposely ignored the call.

"Looks like he got a crush on my friend," Tomlinson says.

At the time, Tomlinson was pregnant with her and Matthew's now, four-month-old daughter Kinsley. And while she "didn't know what to think" of the situation, one thing for sure is that it didn't make her feel good.

"Little stuff gets to me like that," she says while wiping away tears.

"I just feel like I'm not good enough for him anymore," the 16-year-old adds. "I just feel like he might not be attracted to me anymore, so he maybe wants another female instead of me."

Hailey and Matthew are one of the newest couples to join the TLC series, which chronicles the journey of teen couples as they prepare for and face the challenges of parenthood. Follow their journey and the journey of five other teen couples Sunday nights on TLC.

"Unexpected" airs Sundays at 10 pm EST on TLC.