"Our interests" are to be seen as a trustworthy partner in any future treaties we sign, not as a country who sign up to something for brief internal political gains, then almost immediately reneg on it.
A "reasonable person" tries to understand both sides of an argument, and then tries to propose a way forward, rather than constantly bleating about unfair it is that people expect you to live up to the agreements you signed…
Course you do - unfortunately for you, reality does not reflect your thinking - neither Frost (who negotiated the agreement) or Johnson (who drove it through) are Remainers.