So I'm curious about this mostly for people who also have an illness?

So I have Frederick's ataxia which is a immune disease, unfortunately lymphoma has developed from it for those who don't know what lymphoma is don't worry about this question. But I'm kind of stuck on if I tell my friends or not because they have no clue about the progression. I don't want to bring people down so I'm like thinking just like keep this to myself possibly but I'm also worried that they might find out through family. Has been on my mind for a hot minute.
So I'm curious about this mostly for people who also have an illness?
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