[dkitchen]

You've got strengths and are already aware of several variables (exercise, fasting) you can control to increase your well-being and decrease your suffering. I encourage you to keep moving in the direction of ever increasing possibilities. I offer you 3 Immutable Laws of Forward Motion:

1. Pain. 2. Uncertainty 3. Ceaseless Effort

Any attempts to exonerate yourself from these laws will necessarily lead to the sense of being stuck (without options) and hopeless (without possibilities). However if you accumulate skills to embrace these laws, you will increase well-being both for yourself and those you care about.

When you say, "things in my life have been a lot harder to do/achieve than they should...", you're headed for a dead end. Any plan that seeks contentment as a destination is likely to be a dead end. The best game to play has no promise of "win" or "lose". It's the game where you get to keep playing. Evolution seems to be playing that game, and it has produced some fairly numinous wonders. You being one of them.