Filtering obstacles

It's not been so long since I came off the bike, so I am still a little wary on the roads. I know I am, because I get overtaken by other bikes and scooters (spit) a lot more regularly than I used to. I've tried to avoiding filtering whenever I can. Last night coming home, there was a huge queue just short of the Hammersmith Flyover. There wasn't much choice but to filter. As I was passing the stationery cars, I looked for drivers switching lanes quickly, people opening their doors and such like. What I was not expecting was some fucknut pikey to step out in front of me selling roses. I should have ploughed into her out of principle.