Doubting Thomas am I

What about me makes me so full of doubt? i'm too often too afraid to hope for happiness, only because for me it always seems to be a let down. Vulnerable moment coming up... i spent today on the verge of tears, maybe due to lack of sleep, lack of self-esteem, but what ever it was, today it oppressed me.
To feel sad sometimes for me feels narcissistic, because i am so me focused... And i am so tired of me.
There are just those things that keep kicking me in my gut that i thought were gone, but keep rearing their ugly head.