Judy is 1000% right.
Usually atleast 3 times a day I get really, really down. I just have to realize that it will pass be it in an hour or two or even three. Mood swings are just something we've all become accustomed to having.
As Judy said when I'm down I just realize I'll be better in a couple of hours so I use those times to do my busy work. Unloading the dish washer, a load of laundry, take another shower, throw my dog is toy a couple of times. Not only does the time pass but I think being active and not thinking about it makes it go away faster.