I found out my bf is cheating on me with his buddy on facetime

F/21 M/29
My boyfriend and I have been together for almost a year. We are long-distance for a while, and I recently came back from visiting him in France. I loved this man more than I can explain. Despite everything, I genuinely believed we could work through our problems.

For a long time, I've had a suspicion about his relationship with his best friend. There were things that never quite made sense to me, especially how secretive their friendship seemed whenever I was around.

Whenever I'd call my boyfriend and his best friend was supposedly at the same house, somehow he was never around. I never really saw them together. It felt like there was an entire part of their friendship that existed in a separate universe I wasn't allowed to see.
Eventually, I confronted my boyfriend about my suspicions. He denied everything and made me feel insane for even thinking it. I started questioning my own intuition, wondering if I was being paranoid or ruining something good.

But the feeling never went away.
Yesterday, everything changed.
I was on FaceTime with my boyfriend like usual. I was already upset because he was being incredibly cold and dismissive toward me. I was crying, and instead of comforting me, he called me crazy and told me he didn't care about my friendships or family problems.
Then, during the call, something happened that I genuinely don't know how to process.

I realized he wasn't just distracted or avoiding talking to me.
He was having sex with his best friend in his bedroom while his parents were in the next room.
I was literally on FaceTime with him while this was happening.

His friend was there, but he didn't say anything and avoided the camera. My boyfriend was acting like everything was normal, while I was sitting there trying to understand what the hell I was hearing and seeing.
I don't even know how to describe the feeling. I had suspected something for so long, but actually witnessing something that seemed to confirm my worst fears was completely different.

I froze. I couldn't even cry anymore.
And when I confronted him about what I had just seen and heard, he didn't acknowledge it. Instead, he blamed me, questioned my sanity, and tried to convince me that what I was seeing wasn't reality.

Like... what?

I've spent weeks carrying this suspicion, feeling guilty for not trusting him, trying to be understanding, trying to make the relationship work despite how much it hurt me.

Even after all of this, some pathetic part of me was still willing to find a way through it.
I loved him enough that if he had been honest with me, I genuinely believe I could have tried to understand him. I wasn't asking him to become someone else. I wasn't asking him to fit into some version of what I thought he should be.

I just needed honesty.
Instead, he broke up with me, told me nobody would believe me, said I had wasted his time, and repeatedly insulted me while cursing the entire relationship.
And now I'm sitting here trying to understand how the person I loved so much could treat me like this.
I know what everyone is going to say.

“Leave him.”
“Block him.”
“You deserve better.”
I KNOW. I KNOW I SHOULDN'T BE WITH HIM.
But how the fuck do I actually move on from this?
How do you go from loving someone so intensely, imagining a future with them, wanting to understand them through anything... to suddenly accepting that the person you thought you knew might have been lying to you for almost an entire year?

What do I actually DO now?
Because I'm not looking for advice about whether I should stay. I already know I shouldn't.
I'm asking how the hell I'm supposed to let go of someone I still love when the relationship ended in something this confusing, humiliating, and heartbreaking.

I don't want to spend any more time obsessing over what happened, checking whether he's contacted me, wondering if he'll ever admit the truth, or feeling like I wasn't worth telling the truth to. I just don’t understand what happened like I miss my boyfriend the one that wouldn’t dream of hurting me purposely like this guy is literally the devil and it all happened in a few weeks since ever since we went long distance he just hates me and prefers making me cry rather than laugh. I feel so stupid for not at least seeing a sign of his madness like genuinely no one is believing he would ever do such a thing. I am beyond baffled. And he chose the worst time to show his evil side like what the heck dude maybe you should have waited two more weeks yk.
I just want to feel normal again.
How do I actually move on from this? like what the flip I am scared to tell anyone because that would make this real and he would be gone forever. I somehow wish I had more time to love the guy I saw him as for the past months. The boyfriend that I admired and would have really spent so much time loving The worst thing of all this is that he said he truly believed he loved me more than I ever did or could