Hi Paul
Sorry to hear of your travails, I believe the Thames can be a hard mistress at times.
My last bite came on the 1st March 2013. It was a small chub of about 3lb and came at last knockings. My last barbel bite came on 30th July 2011! I let my son land that one, she went 10lb 9oz.
I've only had one blank since so I can't claim it's been a hard slog in that sense, but having missed the whole of last season and only managing a handful of trips the previous one, I'd have to say at this moment in time I'd rather 'enjoy' a run of blanks than sit reading enviously of others' fishing trips from in front of my Mac.
Good luck with the rest of the season, I'm sure all the hard work will be rewarded soon.