JUS' E-MAIL ME: ¿HOW DO I STOP DATING MY BOYFRIEND & HIS BEST FRIEND?

I’m 21 years old my boyfriend is two years older than I and we have been currently dating for ten months now, which has been the best time of my life so far. We hang out with his friends and mine balancing it out, but mostly with his for he's more social and outgoing as I am not. I feel like this complements our relationship well for we both have many to offer in the relationship. 

Most, if not all, of the time we hang out with his fiends he always invites his best friend. We have gone bike riding, drinking, and just hanging out with his best friend and of course we have our own days together. I have been fine with his best friend tagging along, but it wasn't till our 8 months together when my boyfriend told me that him and his best friend kissed once before he had ever meet me long ago. 

At first like anyone would I felt betrayed and lied to. His best friend ever approached me and said to not worry that is was a thing in the past. I thought that was brave of him so I commended him for that. So I put myself in my boyfriend shoes and thought it must have been hard to tell this revelation to me within the first months or so of us dating. So I looked pass the problem and kept the relationship moving forward. A month after we got into a discussion about me not paying attention to him so he said "I'm going to call (best friend) he'll listen to me and we'll have a conversation." At the time he was right i was playing video games and was blocking him out, but we would he say something like that? To grab my attention, make me feel jealous. We eventually continued on, but i was till recently that I now feel very uncomfortable with his best friend around.

We planned a trip to Disney and of course his best friends came with another two of my boyfriend’s friends. Trip was fun, but a few thing did bother me. My boyfriend became an annual pass holder for Disney, his best friends was one already. I did not because it is expensive and i don't have that kind of money to spend for that luxury. He would say things like "Now we can go to Disney more often", "Can wait to go to Disney again Halloween, when do you have off? (Directing to his best friend) etc. At night after the park we would go drink and at the liquor store he bought a bottle because it’s his and his best friend’s favorite drink. To his own defense I am not much of a drinker, but hey it’s a vacation at least be a bit more considerate and ask me if I would like a brink or something. 

We bought each other gift and that sort of settled that mood but I just stayed strong. Last thing that just made me question my relationship was that my boyfriend posted a picture on Instagram with him and his best friend quoting the genii from Aladdin "never had a friend like me" yea that’s cute and all, but where is our picture together it’s been two day and  nothing. I don't wasn't to come off as a jealous person, but it’s hard not to.

I know for a fact if i approach him about this situation or problem he's going to somehow flip it and make me seem like the bad guy and say I'm crazy. He is very hard headed and whenever i try to speak up it ends up into a fight. I truly do love my boyfriend and i do not know what to do. I know that i do not want to lose him. I don't know how else to approach this situation what should i do?

What are your thoughts? 

What advice would you give this person?