Ellen of the CWD forums referred me to this post which was a weird read for me because of how much I sympathized.
Of course, you can't really compare diabetes to cancer, and it's not that cancer is "worse".
I think that a common fallacy among people struggling with something unusual, whether it's diabetes or cancer or being gay or dyslexic, is that other people don't understand at all because they don't have diabetes or cancer or dyslexia or homosexuality.
But most people have struggles. They understand what it's like to be different or what it's like to struggle, even though they don't understand the features peculiar to our own struggles.
And it's also fallacious to assume that a certain sort of struggle is always more difficult than another sort. Being gay might pose a huge problem for one kid, and be a source of misery and isolation, while another kid doesn't really think twice about it. Having diabetes might be the end of the world to you, or it might be a pretty small deal (even if you're realistic about it- I know a woman with diabetes that it's not a big deal for because she's got another terminal illness anyways and is beyond being fazed by the little stuff). Somebody's agony over what she should wear and her embarrassment over her clothes might make absolutely zero sense to me, but it's as real to her as my upset over my blood sugar. It would be wrong for me to say that's nothing- my problem is bigger- because it isn't. It isn't, because the problem is simply that I am upset and that she is upset and her upset is every bit as big a deal as hers.