If your boyfriend says he doesn’t want a girlfriend anymore, it means that he doesn’t want a girlfriend anymore. And his actions are backing up his words. He’s trying to hurt you and he’s driving you away.
My guess is that the weight of eight years is crushing his courage. Deep down, he wants to break up with you, or he wants you to break up with him, but he’s not going to admit it. Instead, he’s going to take the gutless approach of making you feel bad and giving you mixed signals until you get fed up.
Eventually, one of you is going to end this, but it’s not going to be clean. Eight years is a long time, and the odds of you entering into an “it’s complicated” situation with him after the official relationship ends are very high. Be prepared for that and do your best to move on. You’ve had a great relationship and now you need to step away from it as best you can. Please try to avoid the “we’re still hooking up, but we’re not dating anymore” thing. If he doesn’t want a girlfriend, then he should have a friend with benefits either. If you’re smart, perhaps you’ll be able to remain in each other’s lives after months spent apart healing. But do take that time apart, focus on you, and avoid any games he wants to play.