Oh, WOW! I mean... that is just amazing. I was rendered speechless and need a second to collect my thoughts.
I can say that the mindset and faith in destiny plays an enormous role in our lives. By that I mean that we must always approach any problem we have in life with open arms, with the belief that every single thing that happens, happens for a reason. A reason for us to learn and to grow into the person we are meant to be. I know it sounds a little like a cliche, but I will be speaking out of my own humble experiences in life, at the age of already 31.

So here are my 2 cents on the subjects:

I will start at the beggining of your post and say that thinking about our future is one thing that we cannot escape from. But be careful no to entangle yourself in these thoughts and get trapped there. There is no harm in just thinking and imagining the various ways you would like your life to turn out, but if you keep dwelling on it thing can really get out of control. There was a quote I have read that roughly sais "be like water, adapt to the situation and have faith that you would end up where you belong". I really like this saying just because if you really think about it most of the problem we have in our lives are there because of the way we react to the situation, not the situation itself. We must keep in mind that we have the power to change our way of thinking and thus changing the way we react to the situation itself.

Moving on to the story.
I have had a similar (without the happy ending of the story, lol) experience in my life a few years ago, but exchanging messages via smartphone/computer. Having that said I must say that reading the whole story brought tears to my eyes, and I am always happy to hear that kind of story. It kind-of makes you believe in destiny and in true love. I have no other words to describe this story except "true love", just because for the story to develop as much as it did and have that happiness in their lives nothing else comes to mind.
There is something in hearing one of those stories thats just warms your heart and makes you believe again, right?
I just really try to believe that everyone deserves a story like this and that it is up to us to make it happen.
A few notes I must take here and say that, as you said about the generation we live in, is that everything seems warped to the point we dont know what to believe in. People nowadays tend to materialize everything, they tend to not give much(or any at all) credit to the feelings they are having or the feelings other people are having towards them. We all know it and it makes me sad that this is the way people choose to be, but oh well.
BUT we can only gain and learn from the story you told us about Ma'am Leslie and her husband and have faith that God or the Universe, however you want to call it has something bigger and better planned for us than we can imagine.
It does make you think, doesn't it?
But please dont focus on the how or when it will happen, just focus on believing it will!