Soft water and still the same problem? Dang, that's interesting.
KoolKurls is on to something, but even if you don't or can't put it into a protective style, make sure you have someone trim those damaged ends! Not trimming the damaged ends will make matters worse, because even if your hair grows out the hair will continue to split up the shaft.
If I'm wrong, please correct me
I'm currently trying to grow my hair out past collarbone length too, and I just trimmed my damaged ends, so I'll be following this thread to see how you do!!
Oh, and I too agree with AlikaIssa about not doing the puff so much. It thinned my edges out over time. It's been about a month since I put my hair into a puff and already my edges are filling in nicely (with the help of some castor oil).