I have a stable girl friend for nearly two years , recently a
girl who is younger than me appeared in my world ( her attiude and
way she speak ) really assamble to my ex.
I started to feel like chatting with her so i tried to get to
know her more , my friend gave me her contacts , she seem friendly
and I feel comfortable chatting with her at times.
I tried to forget her but she kept appearing in my
mind.
Should I just treat the girl who look like my ex like a friend
and forget her quickly?
The stark resemblance does not signify anything
- it is your attitude and perception towards such visual imaginary
that seemed to suggest your karmic bond with this person. Such
phenomenon is likely generated because of our irrevocable actions
in the past that are generally beyond our scope of control. And
because we can't turn back time to alter our regretful past, our
present and future remained in status quo based on our earlier
decision via freewill.
Albeit the law of causality might be rigid, but our minds and
heart isn't. Hence, phenomenon of resemblance resulted in an
implicit behavior/mindset that served under the theory of 'Time
Machine' (CloUdiSm). Because in the realm where 'Love is blind',
similarity will naturally (and usually automatically) perceived
from the source where it first began and the seeming linkage is
establish, although it pretty much illusional.
I will illustrate a simple example:
There are times when we felt that we made mistakes and regret in
life, with regards to our previous relationship. Equally often, it
might not be mistakes - perhaps we felt that we could 'do more'
(whatever 'more' meant to you philosophically). And because the
manifestation has already occur and we are unable to undo our
circumstances, we shoulder certain unconscious anguish or
bitterness that carries in our soul.
Such suppression are dormant and only brought into surface when
the concept of time triggers a astrological/karmic pattern to bring
forth such situation once again.
Then you might question - why such a phenomenon?
There are two likely reasons:
I) It served to test the foundation of your relationship. Those
who are stuck in the misery of their past will often create the
path of destruction for their relationship of the future.
II) The absence of graduation in prior cosmic lessons resulted
in reiteration of the same chapter once again. What we cannot
master, we learn again.
I suggest instead of first leading yourself into the direction
of asking 'Should i just forget her quickly' - I reckon
you should reframe your question and direct the question
inwardly.
'What does this mean to me and my development in
Love?'
You might want to understand if there's an action/s you wish to
compensate for your previous failed relationship and unconsciously
directing this effort towards this 'proxy'?
Also the identity of your relationship is being questioned as
well.
'What does it means for your relationship and your gf?'
Namely, is your current gf lesser in any aspect than a figure of
the past?
Only with careful examination of yourself, would you be able to
have the clarity to decide your course of action with wisdom.

Cheers