...I Broke My Friend's Trust Because I Was Afraid of Being Alone...

So this is like one of those stories where you feel bad for doing something but you're also kinda scared not to. See, there's this girl named Lisa in my class who's always so cool and popular. She can talk to anyone and everyone...but she's also really nice to me when no one else is around. We've been friends since forever basically. But I'll be honest, the older we got, the more I started feeling left out. It's like I'm still this little kid who doesn't know how to do cool things that everyone talks about...or maybe it's just me? But Lisa has all these other people and when they're around, she doesn't need me... One day after school, we were supposed to work on a project together. We have lockers right next to each other so I could see her inside hers and talking with this guy named Jake who sits at the lunch table with her. They seemed to be joking...and then Lisa pulled out some papers from her locker and slipped them into his backpack. I felt sick to my stomach seeing that. What if they were planning on ditching me for their project and pretending it was all mine? That would mean I'd fail the class...and Lisa wouldn't even bother talking to me again. The thought of being alone in school just killed me a little bit. So, before she could close her locker, I snuck behind her and took those papers back out and stuffed them into my backpack. I hid them under all my other stuff so it looked like they were mine all along. After that, I pretended to look for some notes of my own until I saw Lisa and Jake leave together. The next day in class, the teacher asked everyone to hand in their project work...and as I took out the papers from my backpack, she gave me this weird look like something was off. Then when it came time for presentations, both Lisa and Jake were nervous talking about all these ideas that I knew they hadn't come up with... I'm still not sure if I did the right thing or what to do now. They're probably going to figure out soon enough...and then who's gonna want to talk to me?...