Am I crazy or is my boyfriend oblivious ?

I’ve been with BF for 2 years, we took a break a long time ago. During that, an old mutual coworker tried to take me out. I warned him of my relationship before and he assured me that they didn’t talk and it was just a hangout anyways. UNTIL we went to Wendy’s and he tried to get me to fuck in his backseat in the parking lot. I declined, he took me home, and I ended that next day. Since then, he has tried to hit me up, the last time being in July. (I rejected and always mentioned my boyfriend.) He was blowing up my phone for days and then finally just stopped. I never told my boyfriend because I knew he’d flip. Well he ran into him yesterday and told him this story that he was trying to pursue me and he “never knew” about BF and would’ve told him earlier he had his number. My boyfriend blew up my phone in the middle of the night and was threatening to end it over it. I sent him the screenshots of what I had. I also tried to talk to (friend) and was like wtf? He claims he wanted to “figure out what happened”. But I feel like he’s just trying to rile my boyfriend up since I rejected him because there’s nothing to “figure out” when it’s pretty straightforward that I just wasn’t interested? But apparently my BF, instead of seeing it that way, took his number too. And then he called my BF and told him that too. My boyfriend again started going off on me, calling me stupid and annoying, saying I can’t do anything right, and he’s ignoring me now. But I don’t get how he doesn’t see that this guy is just desperate? Like it’s 5 months later and he’s STILL trying to get to me? That’s obsessive to me. And I didn’t even do anything, I was defending myself when some creep is lying and trying to sabotage my relationship??