Cringe.

I can think of no concept more horrifying than personal immortality and if you disagree I don't think you've thought about it enough.

I'm sorry to hear that you don't want to exist in the future. I do. I have thought about it extensively, and there is literally no scenario in which I consider not-existing better than existing.

There is an essentially infinite amount of creativity and interesting complexity available in the richness of interactions with other people and the things people create. What, exactly, are you "horrified" about?

The difference between "essentially infinite" and "actually infinite". Infinity is a very long time.

No, there is no alternative. Everything eventually dies, so you better make peace with it. The only people who believe that they won't die are religious people who believe in an afterlife (which is a preposterous position) and the people who have their heads or whole bodies frozen because they think they are so special that the future will honor their contracts and revive them.

Both of these are bound to lead to the exact same outcome so it doesn't really matter what you believe but it may guide you to wiser decision while you are alive to accept reality absent proof to the contrary.

s/make peace with it/make war with it/. To the last breath.