Fame
Unfortunately, this is a driving force for many aspiring singers, and some musicians. The love of the music should come first—the fame and glory about fourteenth and fifteenth, respectively. It's wonderful if it happens for you, but you're statistically almost guaranteed never to taste it. Don't take it too hard.
You need to be okay with the idea of acquiring fame on a small level. If you perform at a club and thirty-five people come out to see you, that's pretty cool. You're not filling up Madison Square Garden, but still—it's thirty-five people who have sacrificed whatever other plans they might have had to come listen to you perform.
You may have to content yourself with such small successes, because it may be all you ever get. If more comes to you, beautiful, but don't count on it. Not everyone is Lady Gaga. Can you imagine what kind of a world we'd live in if everyone was?