Fiancés bromance is too much?

So my fiancé and I have been together for 3 years, engaged for one and get married July next year. His best friend has been around since his childhood and they are still somewhat close - he will be his best man at the wedding. They live in different states and they mostly talk over their headset while gaming & although they don’t game as much as they used to, it still seems to be the only thing they have in common anymore. My partner is a Christian man working a full time labour intense job and works over time most nights. His friend is a single casual bartender who doesn’t really give a s*** about anyone/anything other than himself. He drinks, takes drugs, plays games and throws self pity parties (sorry for the vent but it’s true 🙃). Whenever my partner achieves something in life, his friend drags him down & manipulates my partner into redirecting his energy into feeling sorry for him because he seems to be going nowhere in life. He literally calls my partner over 5 times a day and constantly messages him asking to play games with him & talk to him. I understand wanting to be there for a friend but my partner gives into him every time & will even stay up all night playing games with him then go to work the next day for 10-12 hrs with no sleep (which is dangerous in the role he’s in). He even called my partner first thing Christmas morning and roped him into playing games with him!! On Christmas morning!! When it was my first Christmas away from all of my family (they’re all in my home country) - so I spent Christmas morning by myself scrolling through Instagram and Facebook. Am I in the wrong for being frustrated that he keeps going back to his friend and giving him exactly what he wants??? His friend has a very intense personality and I try to get along with him and give the two of them their time together to be friends, but its honestly just too much for me. What sucks is that he is planning to move back to our state in Feb as he plans on going to an acting school and my partner told him (without asking me!!) that he can stay with us for 2 weeks (but I have a feeling he will milk it and stay even longer 😩). My partner even said “if I met him now, I wouldn’t be friends with him” and says that he is only keeping up the friendship because he already asked him to be his best man and doesn’t want to take it back. He will complain about his friend to me as he knows he uses him but still allows it to happen!!! How would you cope in this situation?? I’m honestly getting sick of dealing with his clingy best friend & don’t want their bromance to have an effect on our relationship and drag on through our marriage...Sorry for the vent! Just needed to get it out 😩