Short and sweet, I had the same problem, no pregnancy even with drugs, etc... Eventually I gave up because I couldnt deal with the stress of negative preganancy tests anymore. I lost weight with exercise and completely forgot about getting pregnant. I then was 7 weeks along waiting and waiting for a period that never came, I had no clue I was even pregnant... I have three children now ages 7, 5 and 2
relax, enjoy getting away in september, pets are good but will only remind you of why you got a pet. Yoga is great but nothing beats an endorphin rush from cardio. An increase (or decrease) in metabolism has been proven to shift a women's hormone cycle and sometimes ending in natural pregnancy.
Also, I know this wasn't part of your post, but I can only guess that sex has become methodical and planned. Working on that may help conception eventually also. Relax and start enjoying being a couple again. Start making love not making babies. An increase in sex drive may just be the jump start both your systems need.