It can be hard- but not impossible- to make friends as an adult. Most women don’t have “built in” networks they once had when they were younger (school, family friends, church, etc.), and life is more challenging in your 20s, 30s, and beyond (careers, babies, home ownership).
Think about who is in front of you. Who seems interesting? Reach out. Invite them over (with their kids, if necessary). Be open.