Yep. I'm either one extreme or another.
I have reasons for becoming untrusting. I've had had negative experiences in the past so I'm very cautious with people, I also have some severe anxiety going on. It's not uncommon for people with bipolar to have paranoid delusions, which happens to me if I start having alcohol/ stims/ late nights or just stressing out more than usual.
I can still become naive at times and end up getting into the same situations, so I must also be somewhat cautious.
I'm hardly in control of myself at times though. Impulsive, inattentive, etc.