TTC + Irregular arrivals of AF = constant heartbreak

Sa
I have always had regular/irregular periods, usually the same amount of days in the cycle, just not the usual 28. In high school I took birth control to regulate them. 
When I stopped BC to begin TTC, the first 2 cycles were regular, 28 days.  Gradually the cycle length has increased. Last month was 42 days. Today I am on day 57 without AF and two BFN!
 It's heartbreaking every single time I get a negative. It hurts worse now since I can't accurately gauge when I am ovulating and testing is so expensive. 
I go back to my OBGYN in August to begin fertility treatments but keep hoping I'll go back to her with pregnancy news. 
Anyone else have this issue? Any advise to a soul, desperate to be a mom?