Volatility

I just realised. I am super emotional. Recently.
I'm practically drowning in my own emotions and thoughts most of the time. It is very unlike the usual me. You know, I used to write, to let off steam, but I was either expressionless or smiling, people around me probably only know me superficially,  only people who are important to me will start to know my thoughts, or rather, could tell when I'm genuinely smiling, or just part of the defense mechanism.
But lately, I feel the overwhelming needs to breakdown and cry several times, to run away from everything and everyone. I am wary of everything others said to me. I became paranoid. I keep feeling that I am inadequate for anything good going for me. I turn to writing, but what used to help me channel my aggression, grief or whatsoever, no longer works. In fact, it became worse. I just feel myself diminishing. My emotions are so volatile that I go from being on cloud nine to the deepest part of the valley with just a sentence from others. This change sometimes comes so rapidly that it scares me, because I wonder when I'll reach my threshold and decide to throw myself in front of a moving car. But I just thought it's selfish to do it for my instant gratification, but someone else, as in the driver, lives in guilt all his/her life.
When I thought of this, reminded me of 'Counting Stars' by One Republic.
'Old, but I'm not that old, young, but I'm not that bold'.
Nothing in this world seems to hold any appeal for me anymore. Everything just feel like a living hell every single day. :(