I spend time meditating (not very good at it), analyzing my thoughts, and coming up with rational counterarguments against my irrational anxious thinking. 

Something finally clicks, and suddenly my anxiety is gone. I'm calm and happy. This state may last a few minutes, a few hours, or even a day. 

Then, one small trigger, the dam breaks, and my old fears engulf my mind again. I try to fight back by replaying my usual anti-anxiety tricks in my mind, but it doesn't work, and I spend the next hours to days thinking of some new thought pattern that will get rid of my anxiety again. It's like trying to unlock a door while having an infinite number of keys, and then the door automatically locks itself and the lock changes, so you have to look for a different key to unlock the door again, and the cycle repeats... I don't know if I'm making sense.  

Is my whole life going to be an endless tug-of-war with anxiety? Does it get easier? Am I doing something wrong?