When exiting the nether through the created portal it will freeze the game in a matter of ticks (1-2) with these named setting turned ON, View Bobbing, Fancy Leaves, Render Clouds, Beautiful Skies, UI Profile=Classic, Render Distance 16, Plutonium mode, Show Autosave Icon, Hide Paper Doll, Outline Selection, In-game player names, FOV 80.0753, Anti-Aliasing=4, Texel Anti-Aliasing.

Turning the setting that affect game play (Render-Distance, Leaves, Skies, and most importantly PLUTONIUM MODE) OFF will allow you to have a better chance of survivng the crash. Plutonium mode is great to have but in this instance it somehow crashes the game, i hope this is helpful to you, and yes i know some of this info is irreverent but it may be more than one thing