Keep at it. My friends were almost all married, but they've slowly introduced me to others who are becoming new friends and the opportunities are expanding. I also felt like some of my hope for new friends through some of my GAL activities was just wishful thinking, but lately that has changed. May take longer than you think, but like other aspects of DBing, patience and persistence pay off.
In my agreement with W, I have the kids weekend nights, so I find myself at home with not much to do often when my friends are busy.
But, you CAN make new friends through GAL activities. I just checked and in my FB messenger, 7 of my 8 most recent discussions are with friends I've made since BD. Sometimes, I look around and can't recognize my life anymore, for better or worse.