Originally Posted by merlinextraligh

The problem is you don't understand where the danger is coming from. The vast majority of collisions involving cars and bikes occur at intersections.

A very small percentage involve cars traveling the same direction as the bike.

Thus, while it's possible that riding on the sidewalk would reduce the risk of being hit from behind, it greatly increases the risk of being hit at an intersection (because you're not where the cars expect you, you're coming the wrong direction, your visibility is worse etc.)

So on balance, minor reduction of a small risk (rear end) with major increase of a big risk (intersection collision) makes your risk much higher on the sidewalk.

Don't let your irrational fears lead you a bad conclusion. Rather, look at the statistics for yourself, and listen to the combined wisdom of people who have ridden a lot more than you, and bicycle safety advocates who have given it a lot more thought and research.