People think changing emotions is really hard and limited. They have a bad perspective. These two stories help:
In the UK they drive on the left side of the road, in America on the right side. Alastair (who's British) was visiting America and traveling around by car. This quite a while back before smartphones, GPS, computer maps, etc. Signage was a lot worse. Driving was newer and the rules of the road were much less well known.
Alastair was driving on a small road out in the countryside with no one around. Suddenly another car comes along, around a bend. It's coming right at Alastair! He slams on his breaks. The other guy slams on his breaks. They stop just short of each other.
Alastair gets out of his car and starts yelling. "What the hell are you doing? Get on the left!"
Alastair is mad as hell. He's really steaming. This fool came pretty close to killing him. Alastair's seeing red. He's considering punching the guy.
The stranger gets out of his car. He's mad too, and yelling. He shouts, "The right! Drive on the right!"
And all of a sudden, Alastair wasn't mad anymore. He saw he was in the wrong.
The moment Alastair recognized intellectually that he was mistaken, his anger disappeared. Instantly he felt sorry and started apologizing.
Fortunately, once Alastair admitted he was in the wrong instead of yelling, the other guy didn't feel threatened anymore and relaxed a little bit. When Alastair explained he was from Britain, and they drive differently there, the stranger saw what happened and his anger faded too.
The lesson is that very strong emotions can change in an instant to match your intellectual view on what happened. E.g. if you're mad about someone's mistake, but you realize (with total clarity) that you were the one who made a mistake, then it's common to immediately stop being angry. And it's common to completely stop being angry with no lingering anger and no effort to suppress any anger.
This is not guaranteed. Some people would stay angry. But a lot wouldn't. It's completely achievable to dramatically change emotions like this in accordance with reason.
The second story comes from William Godwin:
let us suppose a man to be engaged in the progressive voluptuousness of the most sensual scene. Here, if ever, we may expect sensation to be triumphant. Passion is in this case in its full career. He impatiently shuts out every consideration that may disturb his enjoyment; moral views and dissuasives can no longer obtrude themselves into his mind; he resigns himself, without power of resistance, to his predominant idea. Alas, in this situation, nothing is so easy as to extinguish his sensuality! Tell him at this moment that his father is dead, that he has lost or gained a considerable sum of money, or even that his favourite horse is stolen from the meadow, and his whole passion shall be instantly annihilated: so vast is the power which a mere proposition possesses over the mind of man. So conscious are we of the precariousness of the fascination of the senses that upon such occasions we provide against the slightest interruption.
In other words, in the heights of sexual lust, people will forget all about sex if you tell them their father died, tell them they gained or lost a lot of money, or tell them their horse was stolen. People are so familiar with the fragility of sexual emotions that they take steps to avoid interruptions.
Read the whole chapter, The Voluntary Actions Of Men Originate In Their Opinions. Actually read the whole book, Enquiry Concerning Political Justice And Its Influence On Morals And Happiness. Godwin was one of the all time greatest thinkers. Not for his time (1756-1836), but period.