How do I make friends in the small town I live in?

I moved to a VERY SMALL TOWN about 3 years ago and I've been struggling to make friends here. I realize that most of the people have lived here their whole lives and their families are friends and they've all been friends for 20+ years so I know that its hard to accept new people into the group. I mostly feel unwelcome, I try to socialize at events for the kids and it seems like mostly people don't want to socialize with us. Even my kids are excluded from things. My kids rarely get invited to parties, only 1-2 kids ever come to parties we throw. It's to the point where my kids don't want birthday parties or anything like that because they know no one will come. I don't really know what else to do. Its really lonely for me and I can tell that my kids feel it too.

Any advice is appreciated.