Can You Really Trust Someone Who Was Once Your Enemy?

This story is from Mahabharata.
Yudhishtira is asking Bheeshmacharya a question.
Should you ever trust someone who has been your enemy once?
Bheeshma narrated this story as reply to this question.
Kampilya was the capital of Panchala.
When Brahmadatta was the king of Panchala, a bird lived in his palace.
Her name was Pujani.
She was very wise.
On the day a baby bird was born to her, the queen also gave birth to a boy.
Pujani was very fond of her own baby and the prince.
Every day she would go out and get two tasty fruits, one for her own baby and one for the prince.
Those fruits were very healthy as well.
The prince grew up fast.
One day, when Pujani had gone to get the fruits, the prince started playing with the baby bird and eventually killed it.
When Pujani saw the dead body of her baby, she became very sad.
She realized what had happened.
She thought she should punish the prince for this.
Rulers are ungrateful, it is in their blood.
They maintain friendship with you for their own purpose.
Once their purpose is achieved, they will abandon you.
Rulers can never be trusted.
They can harm anyone.
After harming you, they might even come after you saying pacifying words and offering you gifts.
But still they can not be trusted.
Look at this boy.
He should have been like a brother to my baby, they were born on the same day.
They ate together.
My baby trusted him.
Still he killed my baby for no reason.
I should punish him.
Pujani plucked the eyes of the prince with her claws and beak.
After having done this, he told herself, 'I have not not committed a sin.'
'I was not the one who started violence.'
'I only retaliated, that is not a sin.'
'A violent deed that is a reaction to a violent deed is not a sin.'
'Even someone who initiates violence, it is often seen that it doesn't affect him immediately from a karmic point of view; it affects his children and grandchildren.'
Then Pujani went to Brahmadatta and said, 'I am going away.'
'I don't feel safe here anymore.'
'I have injured your son and you will take revenge on me.'
Brahmadatta said, 'Don't worry about that.'
'We are equal now.'
'My son killed your baby and you have injured him.'
Pujani said, 'Even if there are moves for a compromise, if an act has been committed out of enmity, then you should never trust that enemy, anymore.'
'An enmity once it comes up can never be satisfied.'
'Enmity is carried down generations.'
'It is carried forward to the next world even after death.'
'One can be safe only if he continues to distrust his enemy even after a compromise has been reached.'
'Once a grudge arises between you and someone else, you should never trust him in your entire life even if it looks like the issue has been resolved.'
'You may speak kind words to me, you may even offer me gifts, but I should not trust you anymore.'
Brahmadatta said, 'I have no ill-feeling towards you.'
'You have only acted in reaction to what my son did.'
'That may be true, but once a harm or injury has taken place, nothing can forge a trustworthy relationship between the two parties.', said Pujani.
Brahmadatta said, 'But we have seen in the past that conciliation and peace have been reached even between warring nations in which thousands have died.'
'They have remained peaceful ever since.'
Pujani said, 'Enmity can not be overcome by any means.'
'It would be childish to trust your enemy even if there is peace.'
Brahmadatta said, 'Staying together, living together, and interacting can dissolve enmity. '
'It can help develop mutual trust.'
Pujani said, 'Strategists have said that someone who can not be conquered by force can be conquered by the show of conciliation.'
'A captured wild elephant is not tamed by force.'
'Other friendly elephants are used for this.'
'If you have been the cause of harm to someone, knowingly or unknowingly, you should not trust him anymore.'
'He may act like a well-wisher, he may have been a well-wisher before, but there will be anger inside him like fire inside wood.'
'It is just waiting for the right opportunity.'
'Once the fire of enmity has been ignited and an injury has taken place, it is not pacified unless it burns down either or both the parties.'
'Your enemy may even start worshiping you but if an injury has occured, then you should not trust him anymore.'

Brahmadatta got philosophical, 'But you know very well that all acts in the world are undertaken by Kala, Time.'
'We are just instruments in the hands of Time.'
'If someone is killed, it is Time that has killed him.'
'The killer is just an instrument in the hands of Time.'
'Time decides who should be happy and who should not be.'
'I have forgiven you completely.'
'I do not have any anger towards you.'

Pujani replied, 'If time decides and executes everything, then the feeling of enmity is also a creation of time.'
'That is also natural.'
'It is in the nature of enmity to seek revenge and destroy the other party.'
'You should not forget that Devas and Asuras have been enemies and fighting each other since ages.'
'If time can heal everything, then why do we give medicine to a sick person.'
'Time itself should heal him.'
'Everyone loves his life.'
'I have caused injury to you by harming your son.'
'No matter what you say, I should not trust you.'
'I see my destruction if I continue to live with you.'
'Even if we live together for a hundred years, whatever has happened between us will not go away.'
'It can flare up any time.'
'Someone who trusts the words of his enemy is as good as dead.'
'Once an act of injury has taken place, the relationship is like an earthen pot which is shattered.'
'It can never be joined together.'
'If you trust a person who has suffered injury because of you, then it can only ruin you.'
'You are supposed to live intelligently knowing full well the situation and circumstances.'
'If your leg is broken, no matter how well you dress it up, you will not be able to run with that leg.'
'If a man plows his field without knowing when the rain will come, then his effort will not guarantee him returns.'
'It is important to understand the changed circumstances and change your course accordingly.'
'It is your own action and inaction that would decide your happiness and unhappiness.'
Saying so to Brahmadatta, Pujani flew away.