You have lack of goals in life, therefore
has little motivation to work towards things. Its a vicious cycle -
people who don't think about themselves of what they like/love,
interest, what they excel, etc will forever remain in this way
until something drastic take place.
You could start doing something that you like, EVEN if it has
little practical meaning like mastering the art of folding Origami
for example. When you excel in something regardless of what it is,
self confidence will flow in. Once you are sure you are good in
that thingy, restart this cycle with another interest/things.

You want relationship to work well? Like common sense told you -
you have to get rid of this dark side in yourself. You mentioned in
your other post, saying that you have positive friends, but you
seldom communicate with others and so there are of no
exception.
People who are bei guan have small social circle - because they
don't feel a need to expand them and they don't feel too good about
themselves to get to know people. Self confidence and attitude are
highly related to the people you are with - a guy hanging out with
the punks will behave like one. Similiarly, staying around positive
people will bring about a change in you subconsciously. 
Start communicating, even if people thinks that you are a weirdo.
Learn to love yourself and take much time to read from books that
could enlighten you and stay positive. Negative thinkings are your
automatic thoughts currently, but its possible to change
them.
P.S: Before you can walk a mile, you have to begin your first step.
Trust me, when you have instill a change in you, you will not only
see relationship differently, but the way you lead and feel about
them will evolve and change. 
Cheers