Advice please?

Bri
Hey ladies! 
So i have a bit of a sticky situation I need some opinion on. So I have a guy best friend. He's stuck with me through so much and I actually consider him a brother. Now my boyfriend doesn't like that very much. We tend to get into arguments over me and my bestie hanging out. We argue, he says he can't stand the idea of me having a male best friend, I tell him there's nothing to be worried about and then we drop it. But then it comes back up again a few weeks later. He's met my bestie and they've bonded. But my bf is just jealous of my bestie for some reason. He says that he trusts me but just doesn't trust him. 
For starters let me say that I have NEVER cheated on anyone and I NEVER will. I know what's it like to be cheated on and I wouldn't do it. Especially with my brother. So that's out of the question. 
Now tonight, my bestie and I hung out and got completely stoned. And it was awesome! We laughed at everything and had a good time.. Up until he started hitting on me. He was hugging me tightly and touching my leg and arms a lot. And just being really flirtatious. I would just laugh and move away for a bit. 
And once the high died down, he said he didn't mean to hit on me. And I said it was okay and left it at that. Then I went home. 
And now I'm here wide awake wondering if I should tell my boyfriend that my bestie kinda hit on me. The only reason why i want to is just to strengthen his trust in me. But I know if I tell him he will hurt my bestie. And I don't know what to do at this point. 
Do I tell him and hope he won't hate my bestie or do I keep it to myself and hold my peace?