I can think of some things. The first is that there’s a real chance that, if you are living an unhealthy lifestyle, it is likely actively fueling the depressed-sounding state of mind you seem to be in. I know when things seem hopeless it’s hard to want to try, but it’s the successes in small decisions like that which can help us claw our way out of these pits.

The next is that relying on the “next incarnation” is wishful thinking that, I think there is a stronger case to be made that it’s more likely to be disappointing than it is an improvement. We don’t know how many realities there are, we don’t know how many of them we would ever see (or if we could ever see others) after death, or whether or not there is anything of “us” after death to experience anything in the future. But if we’re seeing the one world we do know is there, getting worse, then whatever else there is or what we can experience, we now know the total amount of them has gotten worse by this much. Put into more simple terms, we lay in the bed we make. What if you reincarnate/rebirth into a factory-farmed cow for example? There’s only one sure-fire way to reduce the odds of that happening - making the choices that lead to fewer factory farmed cows coming into existence.

Death is not an escape. There is no escape. The only way out is through.

Then the other thing that has fueled some of my own decisions, is that we promote what we do, to others. If I were to smoke cigarettes for example, I would be making it more likely that those in my life, the people I care about, would be more likely to also start smoking. From that point of view, literally every choice we make has consequences that probably shouldn’t be taken lightly.