IndieGirl - I understand how that feels. My OH has been a good sport about it all, but sometimes, the preplanning of it etc, just throws everything off.
Maybe try to have some intimacy without the pressure of having to bd? - and be up front about it - say, we don't have to bd, but I'd like to xx. Sometimes, with the pressure off but still being intimate, things happen anyways.
But yeah, sometimes, it just won't happen. I've been there, just gotta roll with it...especially sucks if they feel sick etc, then there is not much you can do.
FX though for you and this cycle!