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.
Yes! It's about creation vs. consumption. We appear to be the only thing in the universe that has a choice about which of those two activities we want to be primarily engaged in moment to moment. It's a heady responsibility.
No. A completely demoralized person (I think that's a better descriptor than 'homeless') would not experience much delight in life. Demoralization is genuine poverty. It's our duty to reduce and eliminate demoralization in all its forms to the greatest extent possible. You cannot do that with money, houses, or guns (aka govt. force). The character traits that prevent demoralization are courage, forgiveness, gratitude, authenticity and willpower.
But even so... finally, we all die a tragic, senseless, and humiliating death, the ultimate demoralization. So the only reasonable posture we can take towards a demoralized person (or any person for that matter) is empathy and compassion.
You're rich because existence itself is shockingly improbable. Beyond that, you even got to be human, with a human mind, which as far as we know is the most expensive thing the universe has ever produced. Lucky you!
You're poor because one day you will lose everything and everyone you've ever deeply cared for. That's a shame.
Enjoy the few moments you have left. You will have a better chance at this if you stop comparing yourself to others in terms of the milliliters of 'comfort' you can or cannot afford within an OCEAN, a absolute carnival of delight available to all.