Swami Mukundananda
After being betrayed, why do I feel nobody can be trusted, and is that thinking right?
Don't over-generalize from one hurt
Concluding "everybody will reject me, nobody is going to accept me" because one person rejected you is over-generalization. That thinking is defective and leads to negative thinking in the mind.
One such erroneous thinking is over-generalization. Say Kavita rejected Dinesh and he is upset, so Dinesh generalizes: everybody will reject me, nobody is going to accept me.