MY BOYFRIENDS BEST FRIEND CONSTANTLY TALKS SHIT

i love my bf but one thing i cant stand that comes wuith him is his best frined!!! he is hte most 2 faced,immature,alcoholic,liar i have ever met!! hes jealous of our relationship he will call my bf everyday at lik 10 in the mornign wanting to hang out...evn wen me n him r tryign to have alone time!, an he wanted to talk to me the other night n was calling me a piece of shit n everything else with my bf sitting rigth beside n my bf was letting him say watevr he wants..... he doesnt confront him!!! an wen we r faced witha asituation he will ALWAYS buy the bffs story ovr mine an its ssoo frustrating especially wen i no hes lying'!! me n bf hvae had sooo many horrible physical fights ovr it...i dont no wat to do or how to dealw ith it@!!! anyone have any advice