Friends with benefits/ Taehyung + Jungkook FF

why am i feeling like this?

I gave Sarah a tour of the whole college, while she was nodding and making approving grunts every now and then.

"Oh, TAE!!" I yelled, when I saw my best friend leaning against his locker, absorbed into his phone.
"Come with us!" I said to Sarah and started to walk in Tae's direction.

A bright smile was plastered on his lips, but slowly started to disappear as we got nearer.
"Hey Tae" I said, but he didn't answer me. He just kept staring at Sarah. His eyes were bright. I had never seen this expression before.
"Oh yeah uh, Tae, this is Sarah. Sarah, this is Tae" I introduced them to one another before Tae held his hand out in frint of her.
"Nice to meet you Sarah"
She shook his hand but didn't pull back and they stood there holding hands for a moment, until I decided to pop their bubble.
"Um..Let's go then?" Which caused them to break apart suddenly and they laughed awkwardly.

I shrugged it off and started to walk towards our next class with them following me.
The rest of the day was strange. They kept exchanging glances, smiling and flirting with each other. I felt as though I was third wheeling them all day. When I tried to join in their conversations, it always ended with them flirting again. I felt ignored.

I sighed softly as I trudged towards Tae's car. He was already there. Sitting in the driver's seat, waiting for me.
"Hey" I mumbled while opening the door. He winked at me and started to drive.

"Now that we're alone, I really need to tell you something" he said, with a stupid grinon his face.
I just frowned and waited for him to continue
"Sarah is so beautiful. She's like an angel. I feel like she captured my heart. What on earth is wrong with me?" My eyes widened when he spoke the words that i had been dreading. Was he serious? He had only met her today. I thought
"I know what your thinking" he said, breaking my thoughts apart.
"That I only met her today all that crap blah blah blah, but that girl is something amazing"

My heart tightened slightly with his words and i didn't even know why.
Why am I feeling like this?? I just kept silent. No words came out of my mouth for the full car journey, while he was going on and on about how beautiful and captivating Sarah's eyes were. He didn't even notice the miserable tear roll down my cheek.