I’m seeing this guy friend behind my friends backs

Long story, sorry.

Had a friend group, started hanging out 1 on 1 with one of the guys, ended up liking eachother but never said anything because my friends were against it.

One, because it changed the group dynamic. Two, because one of my best friends liked him already.

Told them I’d distance myself from him, but decided to continue texting him.

February rolled around, and he asked me out for Valentines. I wanted to say yes, but my best friend felt disrespected. Solely because I already knew that she liked him, but still entertained things with him to the point where he asked me out. Which is understandable.

I rejected him in honour of girl code, and told him the excuse that I need to focus on school. He was understanding and chill about it.

But then I did something really stupid. I confessed – knowing it would keep him from moving on. I guess I just liked him too much to let him go fully. I said something like “I have feelings for you too, but right now I can’t act on those feelings.”

Once again, told my friends that I’d remove myself from him, text him less and focus on my studies. And I did, for a while.

But ever since then, we’ve started texting again, and I could tell things were different. Things kind of escalated, and now we’ve started using couple names and saying ily to each other.

I’m really happy with him but I feel so fucking guilty for lying to my friends.

There’s about 2 months left of school until all of us separate and leave for uni. I know it’s selfish, but I wanted to enjoy this experience with the little time left we have together.

If this secret ever got out, my friendship with my best friend of 7 years would get destroyed.

TL:DR; caught feelings for a guy, but best friend already liked him. Told my friends I rejected him and stopped texting him, but I actually confessed and did the opposite. Things are escalating between us, and I feel so fucking guilty for keeping it from my friends.