Three years ago I had something called a blighted ovum. Basically an egg implants, you get a BFP but no fetus develops. For like a year after that my cycles and hormones were out of whack big time making TTC hard. I started doing martial arts and am back to somewhat normal cycles. At this point I had pretty much given up on that BFP because we were not timing things great even with OPKs and the like. I started to accept that and I was ok with it, especially now that I'm about a year out to earning my black belt.