"Leaving the Justice League"
One day when Bruce Wayne woke up in his mansion He called for Alfred, his longtime butler. Alfred didn't respond, Bruce called for him again. Waiting for a few moments Bruce went to see if everything was alright. Bruce knocked on Alfred's door, no response, Bruce walked to his bedside. Bruce noticed that Alfred was unresponsive to everything, Alfred died peacefully in sleep due to natural causes. Bruce was in shock, his longtime friend the only member of his family, gone, more importantly Alfred was the only person Bruce could trust. Immediately Bruce walked down to his bat cave and turned on the bat computer and sent a message to the Justice League, titled urgent meeting. When the Justice League came to the Watchtower for the meeting, Batman announced that he would be resigning from the Justice League. His reasoning being that everyone that gets close to him ends up resenting him and shunning him, or they end up dying in front of him.
Martian Manhunter and Superman were the first ones to speak up about Batman's insane proposal. They both though that would put the whole world at risk since he is the world's greatest detective. No matter what member of the Justice League gave their reasoning as to why this was a horrible idea, Batman just sat there and wouldn't rethink his decision, his mind was set on leaving the Justice League. This was a brief meeting. As soon as the meeting ended Batman made his rounds, saying goodbye to his fellow comrades'. The last words that Batman said were "I now leave the Justice League to J'onnn J'onzzz (Martian Manhunter)". Once Bruce returned to the Wayne Mansion he initiated the self-destruction sequence to his home, destroying everything in the process. Months after the explosion Bruce Wayne seemingly disappeared from the face of the Earth. He didn't disappear. Bruce decided to live in isolation. Isolation in a small cottage in Europe for the rest of his life.