You did the right thing, why blame on yourself if
the relationship doesn't work out? In the first place,
nobody say that, even by doing the right thing, the
relationship will be ever-lasting. We all discover new
things about our partner and our relationship everyday - it is this
discovery that made us closer to reality... made us realise if she
is really the one we will be together in the end.
She needed to breathe, not because of what you did, but because she
feels that the relationship is restricting her mobility. Like a
bird in cage, there are things in life where she may like to do,
but the liability of a relationship could tie her down. She may
dislike such feelings - always have to put bf as top priority and
such. This may choke her and she feels enslaved.
So how? What to do?
Two words: Release her.
If she feels her self actualization lies else where for now, let
her go because she wouldn't feel happy if this stage cannot be
reach. You loved her? You must see blessing in her life - if this
relationship cannot allow her that kind of happiness, why restrict?
Has your love gone to such heights yet? Or are you still lingering
in physical possession stage? 
Cheers
