Should I block this man?

So we start the story the first week of January. One of my best friends best friends and I start talking. He’s everything. He plays football, him and I have the exact same music taste, he’s respectful and funny and handsome, the whole works. We start dating in February and all is well until FINALS WEEK when he starts getting all weird and quiet with me, says he thinks we won’t work bc of the distance (we live 25~ minutes away) and we break it off. I find out he’s hitting up some of my friends so I block him. Fast forward to 4th of July, we see each other at a party and he makes a move. A couple days later he tells me that breaking off was the BIGGEST mistake of his life and that he missed me everyday and wants to try again. We start dating again. He hasn’t changed, and starts getting weird and distant again. He tells me it’s bc ‘he can’t accept that he loves me’ and a bunch of other stuff. We break it off again. He starts kinda flirting and trying to arrange a fwb situation. I pull him aside at another party and try to have a serious convo abt where we stand. He deflects and the convo doesn’t go anywhere. I find out later that night from our mutual bsf that he was in love with his ex the WHOLE TIME. He keeps texting me bc we are still ‘friends’ and doesn’t know that I know but it hurts rlly bad when he texts me. I can’t tell him that I know bc I don’t want to rat out our bsf for telling me. Do I block him w no explanation? We also share a friend group.