Why do I only feel the need to post when I'm depressed?

*sigh* Again, a post filled with depression. Today was good!....until not too long ago. My girlfriend was acting like I was sick with the plague. She was acting like something horrible had happened but wouldn't tell me what! All she said was "Stop messaging me." I over reacted like usual, and now I am crying and wishing I had just left well enough alone. *sigh* Jeez, I'm too depressed to even finish this entry, even after hijacking my dad's laptop to do it! Hopefully things will be better tomorrow... ;_;