How do I make friends in a new place?

I am 27 years old, engaged and moved to the Boston area almost 2 years ago. I am a teacher so making new friends my age via work has been difficult. I am looking to make girl friends in the area but am having trouble finding girls my age and in my demographic. I have looked at MeetUp.com but am a little wary/nervous about putting myself out there alone at events. Any suggestions?