I don't like bridges either ... or long spanned freeway overpasses (we have a lot of those here in L.A.). I also hold my breath going through tunnels ... and waiting at stoplights under freeway overpasses.
It's just that any minute something catastrophic is gonna happen and I'm gonna be in the big thick middle of it! Bridges leave you with precious little room to get outta the way, you know?
Heh heh! I laugh at myself, but it's how I honestly feel.