I was once the same way, my parents had always drilled into me the stupidity of most accidents and how easily I could get paralyzed so I grew up terrified of flips. Even though I was always monkeying around on everything and doing rolls before I knew about parkour, even on a trampoline I freaked out when It came to throwing a backflip (Pathetic I know.) But eventually I just made myself do it. That's all there is to it, force yourself to do it that first time, and your fears will be greatly reduced. Find a local gymnastics gym that offers open gym and do it into the foam pit. You should definitely be able to do that, and from there it's only a matter of time and pactice, first landing it on a pad in the foam pit, and building it up until ground level, and finally making yourself throw it on the ground. You're scared because you don't know what to expect, once you get the movement down and know you can do it it'll come much easier. Trust me, even us more cautious ones can get good.
