<human>: I had a girlfriend of  four years over eight years ago. We were great and loved each other but both went our separate ways once we found out what we wanted in life. It was a mutual agreement and neither of us dumped the other.

I focused on my career for the next 8 years and occasionally I would date but nothing serious. It was a lonely 8 years and I have been longing for a partner for a long time.

I recently met a girl who is the answer to everything in my life. We instantly hit it off and it has been amazing. I have never dwelled on my first long term relationship and I haven't missed my ex-girlfriend whatsoever or even thought about her in years.

For some reason, I am constantly stopping myself from calling this girl I just met by the name of my long gone ex. I don't know why this is happening and I don't want to slip. This girl is amazing and I want something serious to come of our relationship but I can't stand the idea that my ex has all of a sudden popped back into my head after such a long hiatus. 
 
I guess my question would be; why is this happening and what can I do to prevent it from happening? It's almost been a week straight of constantly holding my tongue and having to remember her name. Has anyone else every had this problem?

Can you give me the gist of the text in a nutshell?
<bot>: My ex girlfriend's name from 8 years ago keeps popping into my head when I want to say the name of my new girlfriend. I haven't thought about my ex in years and years so why now is she infiltrating my mind?