Almost every flight I have been to, there has been other moms with kids. I once got stuck at Newark for a couple of hours, and it was a blessing to be able to share toys with another mom – both her and my kid got distracted by playing with someone else toys.
It is not hard to make new friends. Pay someone a compliment on their diaper bag, or even better, on their cute kid. Works every time. Start at the gate – often they let all families with smaller children board earlier, which means you already have something in common! And while we are at it, make sure to ask at the check-in if they will let you on earlier with the kids. I love not having to stand in that waiting line, it takes one stress moment away from the day.