exiting after a Mission?

[Guest shinobivsdragon87]

Yo guys, ive got a weird problem.

 

Right so Ive got pretty far into the game, was playing earlier did a Tac mission and the game just exited as soon as i press ok on the "all aliens are dead of blah blah blah", same thing 3 times. so i left the scene and abandoned mission, same thing again twice then it let me go so I saved. Next mission I went on is doing the exact same thing, ive done the mission over about 6 times now keeps exiting.

 

so basically theres no error it just craps out on me. before from crashes ive had error boxes come up etc but this is new its really bizzare. anyone had this before and have any ideas???