How to cope with friends getting married/pregnant - time to leave them?

All my friends are married and pregnant and I'm the only one who is still single. I just found out 2 more of my friends are pregnant today, the other gave birth last month the other is expecting next month, 2 with their 3rd child and I flaked on an invitation for a bday party bec more moms with babies were going to be there. I don't like to be around them because they ask why I don't have any or why don't I get married as if I can pull a guy out of a hat, like they forgot or don't know how it feels like. Should I just stop being friends with alll of them and start all over with new ones or what?