What is passion? How does one get it?

So I'm on the phone with my parents yesterday before heading to see the London Symphony Orchestra at Lincoln Center (if you can go see this performance, go! it's fantastic and the violinist was amazing!), and I let them know that Friday is going to be my last day at work as I was laid off (budgeting, hiring freeze, etc), and they were upset and felt bad. 

(The following is paraphrased, as any conversation between myself and my parents can become quite verbose. )

ADW: "look, it's not an idea situation, obviously no one enjoys being laid off, but all things happen for a reason, and this wasn't a permanent job, it was a freelance gig."
Mom: "Yeah, it's just not a good time to not have a job."
ADW: "Oh, I'm well aware, I have plenty of friends who don't have jobs right now, and they are struggling, but I know they will be ok, and so will I. Hell, I'll get a job at a coffeeshop if I really need to get by" - This is a lie.
Mom: "Maybe it's time you look into a change of careers. Maybe you don't do events or marketing anymore. You know, your father and I were watching tv when we were in Paris and Donny Deutsch was on talking to the founder of Spanx, and we though it would just be great if you could do something like that and be passionate about it"
Dad: "Mmm hmm"
ADW: "Thanks for chiming in Dad. So you want me to invent Spanx?" I laughed out loud.
Mom: "No, if you could just do something like that or create something and be passionate about it, invent something or another."
ADW: "I know that I'm a passionate person, no doubt about it, but I would need to have something to be passionate towards, I can't just go throwing my passion around!"
Dad: "Ha!" (Dad was clearly taking a back seat to my mom during this convo)
ADW: "Something will come along soon enough that I will truly be passionate about...look, I have a lot of  great creative friends who are unemployed right now, my friends Lauren, Chris, Katie, Joe, Ben...we could start an amazing creative agency, we cover the bases of marketing, events, PR, advertising, promotion and finance...feel free to help me raise some capital."
Mom & Dad: "Enjoy the symphony!"

But it's true what my parents said, I too wish that I could be passionate about something career-wise.  The woman who invented Spanx got it right, so did my dad. I have always looked up to my father, he got his pilot's license before he got his drivers license...my grandfather would drive him to the airport so that he could go fly them around! Now, even though he retired from flying, he still works on airline security, something that he is very passionate about and something that he does very well. He's even parlayed it into a fledgling media career as well, he's the Washington DC CBS go-to guy for all things air related, which to me is pretty damn cool!

For me, I love theatre, I love events, I love the media. How can I harness my passion into something that combines all of my interests, something long-term and sustainable? Where is that one thing, that one career that I can be passionate about? Have I already found it but not succeeded? Have I yet to stumble upon it? I'll keep on searching, this I know...