To have or not to have?

I've found in the city I live in that people are somewhat conservative and it's a bit difficult to make new friends outside of work. I soon discovered two reasons why this was:

1) Everyone I worked with was from this city, so they still had their same friends from when they were in Grade School. No room for new ones.

2) I'm at the age where most people have children... and I don't. 

It's point #2 which brings me into my blog. I didn't realize my not having kids was really an issue, until:

There were 6 of us at lunch one day, all women, out enjoying sometime away from the office. During talks about the upcoming weekend, two of the women realized they were going to be camping at the same campground. They were pleased as punch to discover this, making plans to get the kids together. Another had planned on going camping but hadn't decided on a campground yet, so she decided to check the availability and join up as well. Then they turned to the other two ladies and asked if they wanted to come out for the day, all the kids can play and the adults can hang out.

If you counted the math, that's 5 out of 6. I was #6 and was not asked or included during this conversation. Pretty sure I could have walked away from the table and no one would have noticed.

The next time a large group of us were out, one girl was talking about how she was doing a Tinkerbell themed party for her. I happen to have a Tinkerbell cake pan, which I asked if she'd like to borrow. She was ecstatic to find a pan and happy that I had offered.

She then proceeded to invite the other six women at the lunch to her daughter's birthday party. Even though most of them had never met her daughter before and did not hang out after work with her.

I again was not asked. I was fairly shocked by this as the girl in question actually was a pretty good work friend and though we had not yet done anything after work, we were making plans to do so. Also I do have a lot of nieces and nephews that I could borrow on short notice if needed for any age group almost, so if that was a pre-req to go to the party...

Maybe I shouldn't have been surprised, but I didn't think not having kids would be held against me.  Who new it was the equivalent of almost being a leper?