Nest week Hesmondhalgh's character, Hayley Cropper, will be seen committing suicide after a battle against incurable cancer.
The storyline has seen a huge amount of media attention and has sparked the right-to-die debate across the UK.
The actress said she had been surprised by the extent of the press coverage of the storyline because it was tied in "so completely" with her character.
Speaking to Daybreak on UTV, she said: "I thought that was very specific to her and that it wouldn't really impact in this way but it's absolutely brilliant that it's started this conversation about the right to die Bill and so on.
"So I couldn't be more pleased about that because that's all you can hope for that people talk about these things in a real way and a new way, so it's been wonderful".
Hesmondhalgh said the story was "such a responsibility", adding: "I did feel the weight of that but it was a real privilege to do it."
The controversial storyline will reflect the split in opinion in the right-to-die debate with both Hayley's husband Roy and friend Fiz Stape struggling to deal with her decision.
Coronation Street producer Stuart Blackburn said: "This is a very sensitive issue and we will be exploring the effects of her decision on husband Roy, who has a huge emotional and moral dilemma over her choice to die this way.
"Not everyone will feel Hayley's decision is the right one and we fully respect this; for that reason we will be exploring both sides of the debate on screen."
Hayley's final episodes will be aired on UTV on Monday from 7.30pm.