Unhappy Girlfriend

I told my girlfrienr>d that an old flame had contacted me....... and OH SHIT... it hit the fan... she got all worried about What if, What if.. I told her that she was someone that I knew LONG ago, had lost touch with and reconnected... didn't go over well... we've been battling ever since... "How can I trust you" " you're going to want to Fuck her" "what about our future" on and on... I haven't even talked to this person, haven't seen her... we are just filling in the gaps of 30 years of time. She has a family, so do I, I want her in my circle of friends. I want my girlfriend and her to meet. I think they would get along great! It's a Jealousy issue and to be honest, I too would probably have some issues with it... I love my girlfriend. We get along GREAT we have great chemistry together... How do I make her understand that its just to old friends getting reacquainted she was my first love but she has a family and so do I. We just want to be friends..

any suggestions!!

any help is needed