Replying to Overcoming fear

I've always been afraid of unfamiliar features but I feel like it's gotten really bad lately. Last time I was in the park I was for some reason too scared to slide a simple picnic table? And the time before that I couldn't get myself to attempt lip on or unnat slide on an easy box. Blading has spoiled me since I can stall grinds while stationary or moving very slow, but in skiing you either have to take the lift or hike the feature. But this fear even extends to blading. What kind of mental exercises/techniques can I use to stop being so afraid of having a bad spill?