Its purely because looking back is so easy to do, as you can't do anything about it. Like j2 says, we often look back on happy memories (so life does seem better) or even when we look back on the bad times, there's nothing you can do about them now, you can't change how things were done/said, so you seek the best parts out of it. Like for example, you're on a first date with someone you really like and you come out of the loo with your skirt caught up in your pants. At the time, thats the worst thing that could happen, but you look back on it and it doesn't seem as bad as time soothes things out and you're more emotionally detatched. If I had a pound for every time I'd heard someone say 'someday, we'll look back on this and laugh!' - I'd buy everyone on AB a drink! :) ....(but I haven't, so don't get any ideas!) :)