Gmod crashes to desktop while playing multiplayer

Ok it’s been happening for a couple of days.
It’s all fine for about 10 minutes in multiplayer and then if I hit the esc key or the `(console) key, it just closes the game to the desktop.

This is my .mdmp link:

http://dumps.metastruct.uk.to/dumper.py?dump=hl2_140419_crash_2014_7_1T13_56_47C0.mdmp

Please help as gmod is unplayable due to this ;_;

Can anyone help? Really want this fixed :tinfoil: