I can really sympaphise with you, its nearly 2 years since i began ttc, and still nothing!!
For the last few months my cycle days have been off the wall 33 days then 38 days then 29 days,(have been 28 days for 3 days for the last 2 years) lets see what this month brings, obvious im still not expecting!
The last year i been tracking as you say and using o- predictors and still nothing, this last month i said to DH that i needed a break its doing my head in especially when im late and its bfn, i dont think i can take much more emotionally.
i hope you feel better knowing that my menstrual cycle is reeking as much havok as yours, all the best.
Lots a baby dust