I would not worry about it. It might be time for a reality check though.
Step back and take a look at your idea. Does it have legs. Is it something that people want. Can you monetize it. Don't take your own opinion seriously, ask people if they would use it and see ads or pay for it. If you can't find anyone who would, come up with another idea.
Figure out what it would take to get to the next step. If the answer is a boatload of money or a team of people then it may be time to come up with another idea that has a lower bar to clear. If the answer is a couple of months of working nights for the founders go for it.
One more thing. I've been lurking here for awhile and I see the passion and desire to make things happen here all the time. It motivates me to work harder and make it happen for my project. I think this small community is a great virtual community. We can all use it to push each other to succeed. I know I am. I wonder how many YC rejects will succeed? I'm guessing a lot more than normal.
I couldn't apply with my reality. I'm too old. I need too much money. I can't move. etc...
But it does not matter. I will finish my project and I will release it and see if it has legs.
I can't wait to see more new products announced here by the YC rejects. I'll keep lurking...