One

Not everyone has the same level of being sane. Some people after traumas change radically and their insanity scares you.

Being part of the experiment might leave scar on you, but it shouldnt stop you. You have to fight your shadow first, person made off worst side of you, fears, demons you have in you mind. Facing it in a person looking like you is not easy bu you have to fight. Since there will be only one winning in the batlle.