CP -- I know exactly what you mean, and I do that too.

Especially for little frustrating things that are stupid -- like my math homework!! I start crying and thinking at the same time, "Why am I crying?? THis is nothing!" so I just have to keep doing whatever I'm doing and get it fixed so I can wipe the tears away and get going.

It definitely depends a lot on hormones too -- the week or so before my period even sitcoms make me cry.

Unfortunately, it's just the way life works sometimes. *hugs* But it doesn't mean you're weak! And you are not the only who does that!