"We got along well, but our ideas of the future weren't aligned." you said for your first relationship.
I think that's why your current one actually did so well. You must have felt aligned in the ideas or the world and of your lives.
In all my attempts of long-distance relationships this seemed to be the biggest factor because it told you if your partner is thinking about you just as well as himself, or JUST himself.
You didn't mind that she did a year in Australia and because you let her grow just as you needed to grow, it had a chance to work.
When I met my husband 3.5 years ago, it was instantly clear we share the same view of the vision of a future world, not just our future. Of the things we would like to do in order to feel happy (help in some way to improve the future for our children, well, HIS children in this case). For me, it was a general need to fight for a better tomorrow as they say.
That in itself bound us so strongly together, I think we could withstand any obstacle, any distance, any separation over time or space. While I know that he is alive, there is no one else for me. And if there was doubt, I would wait, forever.
I asked myself - how did our grandparents do it? There was war and for years they wouldn't know if the other one is still alive. Are we, our generation and future generations, capable of having that kind of faith to wait?