Teach Me How To Love.(Jughead Fanfic)

Jealousy?

Alyssa's POV
That night I couldn't sleep. I missed the light sound of Jughead snoring. I missed hearing him mumble sounds and syllables. I missed his presence in my room. I missed Jughead. He made me feel safe and I didn't know why.
The next morning I just threw on some sweats and slippers. I put my hair in a messy bun and didn't bother with makeup. I didn't care
When I got to school I felt all eyes on me. "Woah Aly, are you sick?" Veronica asked me. "Nope, just tired." I sighed. " Jughead left because my dad found out he was living at my house."
"Awe, and you miss him." Veronica cooed. "Yeah, I guess. He stayed at Betty's last night." I trailed off. "Oh my god, Aly" Veronica pulled me into a hug. I hugged her back but I didn't need a hug. I needed Jughead.
At lunch I didn't eat. It's not because I wouldn't, but because I couldn't. When I got to the table Jughead was there. He was sitting right next to Betty, smiling and laughing. Great. "Hey Aly, how come you're not eating?" Betty asked me. "I'm not hungry." I tried hard not to yell. Betty backed off. "What's wrong Aly?" Archie asked. "Nothing, I'm perfectly fine." I fake smiled. "No, there's something wro-"
"I said I'm fine!" I cut off Archie. "Woah, Aly calm down." Jughead said softly. I breathed in and out. "Veronica, a word?" I grabbed Veronica's arm and walked her near the building. "What was that?"
"I don't know. I guess I was just pisses that Jug and Betty were acting like they knew each other for years." I rambled. "Aly, are you jealous?" Veronica asked. " I don't know. Ever since Jughead came back into my life I haven't known what I was feeling." I sighed. " You like him, Aly!" Veronica smiled. " I don't know how to like someone. I've never been in a relationship. I basically classified myself as a asexual. All these feelings are new and scary."
"Don't worry Alyssa. When you're ready to tell him you'll know. Don't wait too long because it looks like he won't be available forever." We both looked over at Jug and Betty. They were laughing and smiling.

Why does he do this to me?