Is it just me? I've tried about six restarts, trying out various settings for MC, but I couldn't get past the first day of the mission. Every single time she "crack"ed and game over.
The game should warn you before you begin the main mission if the stability of your character is dangerously low, and let you improve it from that screen.
Also, don't make mistake of rushing into the mission from the first day -- your MC is tired from travel and then if you choose to immediately visit a club you'll end up with stacked attribute penalties which can easily drop MC's stability in the negative. Try to take a day off first, go shopping, attend orientation course and only then see if you can proceed further.
(the lack of feedback regarding MC's current state is something that'll hopefully be addressed down the road)