I totally get it. One year, I had 14 baby showers to attend (helped host about 4 of them). It was pretty hard because I gradually lost one friend after another after their babies were born. I did get to help out one or two of my friends with their newborns, and that was fun because I felt like I was still part of my friends' lives and still important. But things changed even more after I got divorced.
If you enjoy being around kiddos, perhaps you could help out with bath time or when your friends' husbands go away on business? You will still be involved, and you'll definitely come home ready for a nap and be glad that you have decided to remain childfree.
You'll get through it. Just try to avoid baby showers if you can. Those are miserable if you ask me.