My parents divorced when i was 12 and i used video games to cope with it growing up, including rust when i was around 15, back when the game first launched for steam.

Unfortunately, when you decided to divorce, you ruined his development mentally and socially. As all of his friends start maturing and start to enter highschool, your son will start to probably feel isolated and spend more time playing video games.

I just want to say fuck you for not doing your duty as parents, it is the worst thing for a young man his age to grow up with a broken family.

As for a solution, i dont really know if there is one. I can tell you one thing though, this problem you have is not specific to rust. He is probably suffering on the inside , and uses rust as his microcosm.

Video game addiction is almost always a symptom of a much larger problem. Take away the games, he will probably turn to much worse methods of coping.

Now obviously i could be completely wrong here, but from my own personal experience when i was that age with divorced parents thats how i felt. Let him play his games, you no longer have the right to call yourself a parent. You never divorce when you have a child still growing up, idc what the fuck the reason is.