It was stated in the LR novel that came with the japanese release. The western release of LR was heavily censored.
I'd like to see that cause I find it hard to believe, since most directors or producers who make such characters and admit that they are kind of waifu pleasure tend to not associate such characters with any other character in romantic ways, typical selfish desires. Decided to try and find this novel, only thing I found was a cancelled novel that never saw the light of day and it focused on the characters 500 year gap between Lightning's disappearance and return, there was a 3 part novel done for the official website that takes place after LR however it's not eluding to what you're saying. I think you're switching up aspects of what happened in the book to suit your narrative (no offense), as Hope was the one that wanted to see Lightning again(the novel confirms this, it was one of the reasons and ways Bhunz manipulated him into going into abandoned cocoon and used him as a agent to manipulate the savior when she finally returned though he remade him as a younger version, still do to the fact that it's not the real Hope(in a sense) and that afterwards on the new Earth lightning makes for everyone she subsequently disappears again this scenario of lightning x hope getting together seems especially unlikely, as the very last thing said on the matter is that Aoede hopes that Lightning with chance upon Hope or hope(this could mean the character or the idea)could have been a typo and they actually meant the boy, nothing romantically linking the two.