Nobody should make you hide your pain, and I have to say that if my partner acted like that, they wouldn't be my partner for very much longer. That's not to say that it isn't frustrating for partners, though. They will have had an "ideal life" in their head when they started out, and it's likely that they would have wanted a relationship where they could go out and have a good time all of the time, go on holidays, go for long walks - but many of these things aren't possible when you don't know how you're going to feel from one day to the next. Being open and honest with each other is one of the most important things that you can do, because it means that your partner will at least be able to try and understand how the condition makes you feel, and this can certainly be helpful.