False hope that somebody will change
Would someone please help me in finding out a elegant way to describe someone who has fallen for the wrong person and is now desperately looking for slightest (and even non-existent) hint or evidence that the wrong person is changing or improving.
Can be a word or a sentence, as long as it captures the foolishness of hope in such a situation i.e. the wrong person will not change and it is foolish to hope so. Basically something stronger and more specific than false hope.
PS: I am not sure what the best tag for this question is, please let me know and I can update.
There is a phrase, Hope springs eternal (or "Hope springs eternal in the human breast") which connotes unwarranted optimism:
People will continue to hope even though they have evidence that things cannot possibly turn out the way they want.
I'm not sure there is sufficient emphasis on the foolishness of such unwarranted optimism, but it would be used for such a situation, maybe gently, maybe less so depending on how it's said.
Consider, harbor illusions; delude (or fool or deceive or kid) oneself (about someone/something)
deceive oneself
[transitive] deceive yourself (that…) to refuse to admit to yourself that something unpleasant is true
You're deceiving yourself if you think he'll change his mind.
Oxford Learner's Dictionary
Many athletes can't find richness or meaning in life beyond their limited identity. ... their skills are declining, and they harbor illusions about career longevity when reality suggests it is time to move on.
Sports Heroes, Fallen Idols
It didn't help that I'd been harboring illusions about Jim, on and off, for two years.
Also, build up false hopes (about someone/something)
I am anxious not to build up false hopes (= to encourage people to hope for too much).
Oxford Learner's Dictionary
A leopard can't change his spots
A leopard can't/doesn't change its spots. something that you say which means that a person's character, especially if it is bad, will not change, even if they pretend it has I doubt very much that marriage will change Chris for the better. A leopard doesn't change its spots.
A leopard can't change its spots. (n.d.) Cambridge Idioms Dictionary, 2nd ed.. (2006). Retrieved April 17 2016 from http://idioms.thefreedictionary.com/A+leopard+can%27t+change+its+spots