i've been through similar experiences.....or i can go from extremely sad to angry in a flash....i would probably force yourself to be involved in the world.....take a bike ride or exercise, read a book or call a friend on the phone....watch something funny.....it mat not make the depression go away but it was kind of something that i did to not feed the deprression

Well I do not really have any advice but you're not alone there if misery likes company....lets do cyber coffee....

My favorite author once said, "if g-d could make anything better for you right now, he would. Today is the best it can be." If you think about that statement (I do), you begin to see that maybe things that go wrong are there to steer you to a better place. embrace the wrong with the right and the good with the bad. don't beat yourself up for something that happens that should be different. it should be what it is. the more you say and the more you look for the silver lining in things and the value or things they can show you, the better you might feel. i get moody too but only when Iblame myself for the turning of the world.

I think a lot of it depends upon the cause-

Are you borderline? PTSD? Rapid cycling bi-polar?

Until you know the reason, it's difficult to help the situation.