Often when we behave badly it’s because we’re caught up in our own experience, overwhelmed by stimulus or circumstances and are either unwilling or unable to separate our rationality from our emotion.
Sometimes we do things to drive others away or to protect ourselves from things imaginary or real.
Sabotaging the situation may be to engineer the downfall of that we expect to fail; thus we might be able to soften the blow, lessen the impact, or at least keep the disaster in the realm of known evil rather than suffer the possibly worse and unknown evil we so hysterically fear.
The fear of failure or worse can drive us to sabotage potentially successful endeavors and relationships.
Fear rules the weak while hope is a skill of the strongwilled.