History is a teacher
I briefly dated my friend F when I was a senior in high school and he was a junior. My best friend had started college and I was still finding my place in school without her. Lunches while I dated F included his group of friends and even though our relationship ended fairly quickly, his friends didn't ostracize me. While I didn't have their shared history and sometimes felt like I was in a different world as a senior facing college applications and graduation, I appreciated being included when celebrating the holidays and eating otherwise lonely lunches.
My attraction for PJ was instantaneous and I plotted to catch up with him at the movies the night I met him. After my first dinner with his friends, I was automatically included in their group. Despite not being his girlfriend for another year and a half, and even after our breakup six months later, I lived with friends that were originally his and was there to celebrate when two of them got married.
Today at the end of the day my newest teammate at the office came over and chatted with me. Thus far she has kept pretty much to herself, save chatting and playing Ultimate Frisbee with her friend from college--the guy I went out with last weekend.
Looking back at my past, I see one possible future playing the role as the older and wiser girlfriend like I was with F's friends. If I'm lucky, perhaps I could end up with lifetime friends like those I gained from my attraction to PJ.