...really excited? Like can't-contain-it-heart-beating-stomach-fluttering excited?
If you can't remember when it was that you were excited about something, it's time to try something new. It's time to push yourself a little and see what you can do. Try something that seems risky.
Here's an assignment: e-mail someone you really admire, just to tell them how awesome they are. Even better: ask them a small favor, see how/if they respond.
Ask for something for free that isn't for free.
Start something exciting, and share it with someone.
Step out, take the risk, and make art that connects with people.
It's the best way I know to get excited about life again.