It's probably the inefficient way of thinking. It's valid, though not all that great thinking about "Why can't I be happy".
For me, I know why and it's not because I hate the world or hate people that annoy me or hate people that break promises (well anymore). I simply found out that it hurts a lot less to simply not care. I don't expect people I've known to not be nice to me, no disappointments. I don't expect people to remember my birthday and such, no disappointments. I don't expect people to keep their promises to me, no disappointments. I don't expect people to stay by my side no matter what, no disappointments.
Rather sad way of thinking to most people around me, but it's what has worked for me.
[x] plays games [x] has dark hair  Wears a lot of black [x] 5'9" to 6'5" in height [x] knows another language  knows how to cook [x] likes ramen [x] likes alternative rock [x] favorite color is blue [x] watches anime [x] dislikes Paris Hilton [x] has NOT read Twilight series [x] replies to most PMs [x] literate when on da computer lulz
2 points for every x. [x] taller than 5'8"  sexy accent  likes metal [x] does not have short hair [x] is understanding of fangirlism [x] likes math  kind  can lead a dance [x] likes L more than Light [x] has watched Death Note [x] can play an instrument
3 points for each x.  plays guitar  has a cute smile  funny  knows how to treat a lady  can be romantic [x] likes sci-fi  likes cheesy lines  will not kill spiders  can sing [x] can ignore any strange outbursts [x] doesn't freak out easily  is a freakin genius