I hate how common this strawman argument is. Saying atheism is a religion is like saying being bald is a hair style. We are comfortable in not knowing what happens when we die, as you say, we speculate that nothing exists but we don't claim to know unlike religious people. We reject your positive claims.
Atheists are people who rather the bitter truth than a comfortable lie. We don't choose to believe or not to believe. We can't make ourselves believe something that's clearly bullshit. This whole post is asserting that we subscribe to your simplistic bullshit that everyone "must" believe in something as to what happens when we die. Well I don't believe anything about what might happen since the only way I'll know for definite is when I pass.
About constantly thinking about the worst outcomes, you should research stoicism. The philosophy is that we should become comfortable about the worst possible outcome and be able to face it. That way we are ready if it happens and anything less than the worst it a good outcome.
Also too much sugar intake does lead to type 2 Diabetes. Eating sugar causes our bodies to produce a hormone insulin and over time we become immune to it and thus can't produce enough which means we have too much sugar in our blood. Watch FedUp on Netflix or the Joe rogan podcast with Gary Taubes.
RE: Why it is impossible to live life without "religion"