Rough times come and rough times go. Sometimes it seems all times are rough and in hindsight, some weren't. Sometimes, everything sucks in hindsight.
Go to the gym every time you are able and congratulate yourself for pulling it off. Don't go when you are not able and congratulate yourself for being good to you. It's not always easy, but if both outcomes can eventually feel like a win, then you get some wins in the list, make sense?
Happy Birthday!