This is a classic mistake! Although 100% understandable. A variation on this is the reason why writers have the saying "kill your babies" -- be wary of that idea that you are really in love with. That love is awesome, but it also can easily blind you to harsh realities.

I did want to clarify my earlier comments, though. I think what's important is to have multiple revenue streams. We (and I!) tend to think of revenue streams in terms of products, but it doesn't have to be. Revenue streams can also be returns on investments, apparently unrelated services, or whatever you can imagine. The point is to not get all of your nickles from the same pocket.