If relationship is a scale - our essential tasks
on hand would be to keep the weights on either side equal.
Love cannot always be determined by mind logics - this conflict
that you both are having is due to the differences in preception
and definition of your relationship. One is more like a mother than
a mate - while the other longs for a simple girlfriend that respect
personal space and freedom. 
You mentioned about your lonely life and small social circle - this
is true. Let me tell you, one VERY IMPORTANT element to maintain a
lower risk long-term relationship is to have life outside that of
your boyfriend. The dependancy onto him is about 50% of the
difficulty - rather in terms of conversation, it will gradually
become dull. Relationship is gradually crystallized into routine
form. And when problems with bf occur, you have problems finding
people to pour your sorrows too. 
All these points are invisible daggers that lay ambush within your
relationship.
Under the seventh law of Love - Love always wants more of itself and Love
always brings up everything, but itself. As time goes by,
issues that doesn't exist in the past surfaced - what special
motivation do you need to conceal all these flaws that he once hide
during courtship or honeymoon period? Only love and the desire to
improve can change them willingly - if not all is futile. He showed
his dissatisfaction of your attitude towards the relationship and
chose to shower blames then to reflect upon himself. (I am not
saying that anyone of you is at fault, however, since you both are
already together, is it a must to point fingers? This relationship
lacks the combination effort to go through problem and solve them
in unison.) 
Ladies, Yunhaier has one good advice on how retain your man - let
him know how valuable you are to people outside and if he is
foolish enough to dump you, everyone else would fight violently for
your dates. In Art of Seduction: Everyone wants things that are
highly desirable. Your man feels that you can't live without him -
because simply, like what you said: 'you are needy to him.'

And - He knows it.
Expand social circle gradually (not aggressively) and take up
interest course/classes to widen your knowledge. You must have life
outside him - you must instill confidence in yourself and grow less
dependant on him. If things is really getting on well - he will
instead cling onto you, not the other way around, and would be more
willing to let you 'mother' him. 
P.S: Don't shut contact with him totally and don't feel that
'mothering' him is the wrong approach of love. The problem doesn't
lies with you - its with him, therefore, there is nothing wrong is
showering concern. Do your duty as a girlfriend, yet balance your
life onto work and friends-outside-bf. You know you have succeed
when the scales is balanced equally. 
Are you a Cancer?
Cheers