How about doing some night classes, they don't have to be anything academic, just something you like, check out your local college of further education, the lists of courses are endless.
You could also join a voluntary group, or local dramatic society if that takes your fancy.
There are also plenty of holiday firms who cater for single persons (not club 18-30). I went with Friendship Travel this year and had a fantastic time with people I had never met. Something like this will give you more confidence in yourself and broaden your horizons, Go for it girl and good luck.