Finally able to summon the Wither and the game lagged violently, causing my death and loss of all equipment without any chance of recovery. Now I cannot enter that portion of my world without extreme issue. I was very much looking forward to this battle and feel cheated. Is there anything that can be done to re-do/undo this situation so that i can have my battle properly?

If it matters at all; I am still a bit of a noob so this loss is extraordinary for me. Hours upon hours of play spent gathering the best gear wasted and I could do nothing about it