I wonder if the distance can happen gradually, organically. No hard feelings, just a slow growing apart. I am not sure if it's the right way or the best way, but it has worked well for me because I don't like confrontation. An unreturned phone call here, some cancelled plans I forget to reschedule there. Sometimes, in the time of less contact, the other person changes in some ways too and we organically grow back together when we're ready. But sometimes not.