I understand exactly how you feel. My daughter is two and she has always been very social with other children. Most children that we have met haven't been as interested in socializing as she is and when we do meet a friendly toddler, the parents don't seem too interested in encouraging the children's interaction. Maybe some parents are shy themselves or maybe they don't see the value in children socializing. In any case, we have also had a hard time making friends.
In the past, I have joined various mom's groups and gone to mom and tot classes without much luck in meeting good friends for myself or my daughter. Recently I joined Mom's Club of Fairfield and went to a playgroup for the first time yesterday. It was a great experience. Finally I think I have met other very friendly moms who want to encourage their children to socialize. Unfortunately, now I think that my daughter has given up on other kids. She has been getting less and less outgoing at the playground over the past few weeks, probably because she has had a few bad experiences. About a week ago, a little boy made a scary face and yelled at her after she went up to say 'hi' to him. It was the first time that she ever came to me and asked to go home from playground. Hopefully she will start to get back to her old self if I can find nice kids for her to play with.
My advice is to keep getting out with your children to socialize and try a few Moms groups. There are other mothers out there who want to make friends for themselves and their children. Let me know if you are in the Fairfield area.
all the best- B.