How to deal with a complaining pregnant friend?

My best friend recently found out she's pregnant. We both more or less started trying around the same time (3-4 months ago). She's now in the morning sickness stage, which I completely understand is horrible for some. My struggle is, lately the last few days, she'll comment on how horrible it is, or how much it sucks and it honestly stings a little and makes me sad. I don't know how to let her know that while its hard, I'd rather her not make comments to me about it. In my mind, it feels a little ungrateful. Anyone have any experience with how to delicately deal? Do I just deal with it on my own internally or should I say something?