I was heading into a new decade of my life feeling strong about my career, my life accomplishments and my relationship with my partner. But when he asked me who I wanted to invite to my birthday party, my mouth opened and I let out a long trail of ummms. In my early twenties, I was a friend-making machine. I was the president of my person sorority in college and spent very few hours of any day alone. When I moved to New York City after graduation, I joined sports teams and went to meetups and had something called friendship circles, with different groups of people to hang out with whenever I wanted a full social calendar. But then something changed. A lot of my friends got married and had kids while I was still on the first-date trail. Some of my friends moved states away and our conversations grew stale and we rarely saw each other.