Usually, when you get an idea, we get emotionally connected to them. What happens when we get emotionally connected is that we loose the ability to see through all aspects of the idea.
How to address this?
Here is a simple exercise to look at the idea objectively.
Document the idea completely and as much detail as possible. Once you are confident that the idea is documented in detail, we start the exercise.
For one complete week, keep thinking on the idea and only look at positives of the idea. Only positives. Be as optimistic and positive about the idea. Keep documenting all the points you can think of. If possible share the idea with your friends or closed ones and ask them to also share their optimistic thoughts. Document them.
The following week, only identify all the challenges and pessimistic thoughts about your idea. Now, find another set of close friends and family (who have not been part of the previous week). Ask them to critic your idea and document all of them.
Now, objectively look at all the optimistic and pessimistic comments and club them to the respective components of the idea.
Look at the results and by now you will understand if you wish to take the idea forward or not.
In short, if you have to kill the idea, do it liberally, but not for any other reason.