although love is about loving a person for who he/she is,
sometimes there has to be sacrifices.
you may have been a person who has close girl-friends like A.
that's is very you. maybe you don't mean anything. just platonic.
But because you once had a short stint with A, you're like labelled
forever. That's just why your gf feels that way.
however, your gf is not wrong either. anybody would have been
upset with his/her partner being more concerned with another than
him/herself. She would be worried one day you might leave her and
get together with A. Honestly, she also don't understand that, even
if a person who doesn't have a close girl-friend like A, a person
could have found someone else also if there were to be
problems.
A relationship isn't about You or Me, its about
We. it's not like asking you to totally ignore A, but to
restrict yourself having so much things of memories with A. Surely,
you could have created a CD with music that you and your gf
shared?
If you can't sacrifice a tiny bit of your friendship with A for
your gf, it just means that you're not trying enough for her, or
she isn't as important as the friendship of A. Then again, if you
have given up on friendship for someone before and yet there is
still insecurity, something is really wrong.
Ultimately, think about who is going to walk the path with you.
Not your friends mostly, but your partner.