This is a good question...
Learning about panic disorder, so I understand what's happening to me
Initially, medication helped me feel like myself again and relax enough to work through it
CBT helped a lot at working on the underlying issues that cause me stress and figuring out better ways of thinking
My family/friends being supportive
And this may sound weird, but it helped push me to expose myself to the tougher stuff when my doctor and this site said flat out that avoidance doesn't work. On a follow-up appt 8 months after my diagnosis, my doctor said that I wasn't doing everything I could to overcome this unless I got on a plane (my greatest fear and site of first attack.) I was mad and left his office, picked up my mom, went to the airport, booked tickets for a flight leaving immediately to the closest city, repeatedly told myself I could do it and wasn't going to let panic stop me, and the flight went great. I may have been mad when he said it, but in the end, its made me realize everytime a new fear comes up including flying, that I can do it someday. And so can everyone else on this site!
Ariel