To add to my post, I think the way that it is viewed, is if there isn't a chronic lung issues, once a child is 12 months old, the chance of severe complications is low. They may get sick from it, but they are strong enough to fight it off, unlike an immune compromised 1 or 2 or 3 pounder. Additionally, almost all children get RSV by age 2. Some get a mild case, other's get downright sick for a week, and less commonly some have to be hospitalized for breathing treatments. It's a cold virus, essentially, but it can wreak havoc on immune compromised preemies and those with lung problems. I know I was extremely worried about not getting the second season of synagis, because I thought it was what kept DD from getting ill her first winter. Certainly it was important, but so was regular handwashing, sanitizing, and making smart choices about where I took her. She did just fine her second season, having only one or two colds. Synagis isn't a cure-all, and babies, especially those past 12 months are often crawling and getting into everything, so they can get into lots of other illnesses and viruses that synagis doesn't prevent, and that are equally as dangerous: flu, rotavirus, stomach bugs, colds, etc, as well as those same bugs which we can bring into the home.
Anyway, many of us have been there with the anxiety about the second winter. You aren't alone!