A long time ago i saw this anime that involved these two people who had feelings for each other and always dreamed of going into space exploring. The girl whos dream came true got to ride this mech around in space, killing stuff, exploring, but leaving the person who she was in love with back on earth. The only way she could get in contact with was by text messaging/email i believe. As she advanced further and further into space, it took longer and longer for the messages to arrive. It went from days, to weeks, to months, to years just for a message to be received. I cant remember the name of the anime. Anyone? I tried searching already. I think this was an anime movie.
the title is "Voices of a distant star" by Makoto Shinkai. he also made the movie "Place promised in our early days" and it is pretty well known cuz the movie was pretty good.