Aw, I completely get the heart not being in it thing. Somedays, I look at my reasons for losing weight, and I look at a cookie and I just want the cookie more, no matter how awesome my reasons for losing weight.
Someone gave me a quote that I thought was pretty fantastic, even though I can't remember who said it or who referred me to it:
The best time to plant a shade tree?
Twenty years ago.
The second best time?
Today.
Best of luck to you!