I think first you need to pinpoint exactly what it is you are afraid of. I seriously doubt it is the longarm itself. After all you didn't spend the kind of money a LA costs without actually trying one out did you?
Are you afraid of ruining fabric? Solution: go to thrift store buy some sheets and blankets to use as practice pieces and batting. Small investment and that should eliminate any fear of ruining anything. After all, you more than likely spent many thousands of dollars for your set up, what is $10 or $20 for a couple of old used sheets and a blanket? Loads of practice time on one set of sheets with a blanket in between for batting.
Are the expectations you set for yourself way too high and thereby making you afraid of failure? Well the only way to get over that is to do the above. I think it is safe to say every single LA quilter out there who does handguided (not a computer set up) started out making squarecles instead of circles, feathers that looked like they were from some mutant alternate universe or jumped out of a Salvador Dali painting and flowers that looked like a toddler's first attempt to draw with a crayon.
Are you afraid you have wasted a truckload of money because you will never be any good at this? Again, you will never know unless you start and if it doesn't work out for you, you can always sell it. But you have to try. Nobody is ever good at anything the first time they try it. You had to crawl before you walked. You had to learn to wobbly walk before you could run. And you fell down a few times during the whole process. Same with riding a bike, same with learning to write, same with everything. It takes a lot of tries and practice before it becomes 2nd nature.
Quit comparing yourself to others, turn off the computer and go to your LA and load a practice sandwich. Make loops squarecles, quilt your name in cursive, write out the alphabet in quilting. Who cares if your P looks like a Q or your M's look like deformed camel humps. Keep trying.
I went out and bought a bunch of pads of cheap newsprint paper. The biggest ones I could find like 14" x 17" and bigger. Got myself a bunch of pencils and doodled, doodled, doodled. I wanted to be good at feathers so I drew feathers over and over and over again until I could do them in any direction and I was happy with my drawings. Amazing how much muscle memory took over, it was like signing my own name. Doodle and draw whenever you are sitting idle, like watching TV or talking on the phone. Pretty soon you will be able to transfer those doodle drawings to the LA.
Seems such a waste to be so blessed as to be able to afford to have one and not even try to use it.