Junk Food Around the House

In general, I think I eat fairly healthily, but there are those days when I come home and realize a bag of something salty or fatty or generally nutritiously deficient has come along with me from the store.  Does this happen to anyone else?  No?  Just me then.  Full disclosure, I'm actually eating a piece of dark chocolate (my after dinner treat) right now.

I don't beat myself up over these occasional splurges; I see them as a nice treat and not a shameful encounter.  But it does seem that one of the best ways to avoid eating too much junk is simply not to purchase it in the first place.  It should be that simple, right?  However, I think we've all been in situations that make that harder said than done.  For instance, I share my home with a lovely man who has some very different ideas about what treats should come home from the grocery.  I can usually get around this problem by thinking of those snacks as 'his' and not to be touched, but it's not always easy with something delicious staring at me all the time.

There are lots of other reasons we run into food we'd rather eschew in everyday life.  Family, parties, the need for portable snacks and lunches, hectic schedules, and random cravings can all bring us into contact.  What tips and tricks do you employ to keep your diet healthy?  What's your biggest food downfall?