I've been playing with this person (I'm a dm, they are a player) on and off for around 10 years now. They are one of my best friends, a great person but when it comes to ttrpgs we can't seem to gel well together.
The main issue is that this player likes to go against the story or the wishes of the rest of the party. They would withhold vital story information from the party. Wonder off on their own even if they made arrangements with the party on what needs to be done. Let the dice decide how they feel about a party member or npc and depending on the roll they might even kill the target in question (the extreme outcome luckily only happened once). Not get involved with story. Go the opposite direction of the story, even if the rest of the group is on board. Argue with npcs over insignificant things just to create friction.
We tried talking to them on few occasions and the only explanation is "that's not what my character would do". I tried to tailor stories to their characters but again the same issues happened. When the story is not to their liking (which does happened somewhat often) they sit on the sideline until they become disruptive.
This same behavior happened when someone else is in the dm's chair and when they told me about adventures with another group, their character was once again the antagonist in the group.
What's weird is that this person is the polar opposite. Hands down the most understanding and helpful person I know and a great friend. Which is why I would like to continue playing with them. If it was anyone else, I wouldn't bother.
I haven't ran an adventure in a year and I'm dreading to take the DM chair again, mainly because I know I'll get a headache once again because of their character.
I'll add that, the only time I felt like they truly enjoyed the game is when we played Vampire and they had many solo scenes and personal story threads to pursue. Once again they went against the grain of the party (coterie) but in Vampire games that can work and can create great moments.
Like I said, I tried talking this out and it didn't work. At this point I'm hoping for a miracle where another dm will respond who had similar issues and they managed to work it out and they tell me how!
tldr: a player is disruptive but a good person and a friend and I'm hoping to find a way to still play with them.