This I know for sure...

Some friendships withstand time and distance and some don't. I recently had dinner with a couple friends I hadn't seen in two years.  It was like no time had passed at all.  Though we had emailed each other from time to time, we didn't keep in touch on a regular basis. When we met for dinner, it was as though we'd just seen each other a few days ago.  We laughed and caught up with each other's lives and had a great time slipping back into our old friendship like a well worn pair of jeans.  We promised each other we wouldn't wait two years to get together again.  But if we don't, I know when we do get together again, it'll still seem like no time had passed at all.