It is new wheel time and also maybe time to lose some weight. Get a new wheel with a much higher spoke count and make sure it is double walled. Hand built by someone who knows what they are doing or at least working with them is always better than a machine. You have to keep in mind your rear wheel is carrying you and your gear plus dealing with the stress of disc brakes and shifting.

While I understand that taking the full Encyclopedia Britannica gives you plenty to read and you can whip out facts when needed, you shouldn't carry them on tour. Nor do you need to carry your grandmothers cast iron dutch oven. I am a chronic over-packer but man you have me beat by at least 20 pounds. Send stuff home or if staying with a friend have them keep it or donate it. You will thank me.

Good luck