I was very scared at first. I was hit by a car door when I was 14, and didn't get right back on the bike (I was in my mid 30s when I really started riding again, and I'm 43 now). So, I had some issues to work through.
If you have a bike path, use it. Try to go when there aren't a lot of people, I find the middle of a work day is usually perfect. I rode one bike path back and forth until I knew every crack in the pavement. I rode for a couple of years with my seat too low, just so I could put my feet on the ground. Raising it the the proper height was done in increments, as I was ready. I did everything that way, as I was ready. I'd let myself master a skill, then I'd work on the next one. There's a lot to learn. You don't need to do it all in a day. I should add, I never fell, well, not until 2 years ago, cornering too aggressively on sand. Let's say, I've come a long way.
After my fall, I felt totally pumped up, and excited. It wasn't as bad as I'd feared at all.
Oh, and if I could do it, you can do it.
'02 Eddy Merckx Fuga, Selle An Atomica
'85 Eddy Merckx Professional, Selle An Atomica
'10 Soma Double Cross DC, Selle An Atomica
Slacker on wheels.