I don't totally disagree with you...However, she has never had trouble saying no before

Well it seems as if she's having trouble saying "no" now.

and like I said she is the one who suggested the sitter...The only mistake I have made was to be insecure and ask about it again.

OK, so now you know not to appear insecure.

I just am not good at sitting back and making like I have a great life going on. My life is ok; but I get to where I think if I go out with her once in a while, that we will make a breakthrough....I just don't want to do it too often until I know whether I am being used to go out or if like she told me Saturday that she is lost and confused.

OK. You don't have to make like you have a great life... just make it as great as you can for yourself and you don't have to share any details about it... but do look to make it better for yourself.

Insofar as her motives go, you'll be able to discern that more clearly with time and if you take a step back to see clearer.

Perhaps set a decent deadline for when she needs to let you know about the show, then stop mentioning it altogether and see what happens. Expect nothing. If something happens, then great, be delighted. If nothing happens, it's not the end of the world. And... there is better coming, whether with her or not, I believe that, but you have to believe it too and get ready for it.