Giant doily rug

I'm still working on my crochet doily rug using the wool I bought at Bakewell Wool Gathering and I really hoped that it would be finished by now, but it's caused me no end of bother. I've started it and then undone it so many times that it is really is the incredible shrinking rug. I initially followed the pattern to the letter but it just wasn't working for me. It started ok but after a few rows it went all fluted as there were just too many stitches. Now I'm not following the pattern except in spirit and checking regularly too see if it is becoming baggy and wavy (and occasionally ripping back the odd row). Having said all that, I still like the look of the rug but am a bit concerned that it is not stiff enough and has too much stretch. I really don't want to create a death trap of a rug so am wondering whether to try shrinking and felting it a bit in the washing machine (maybe a bit drastic), or to create a fabric or crochet backing for the rug to firm it up. Hmmmm, must ponder this further. Mind you, I might never finish the darn thing!