Not looking forward to the weight gain, myself. I worked really hard to lose almost 70 pounds a few years ago, the majority of which I put back on when I met my husband. He doesn't care- in fact I think he prefers a little more meat on me- but I DO care, and was already getting pretty unhappy with where I was at when I got pregnant.
I've had to try (hard!) to remind myself that I'm making a person and nourishing not only myself but that little person as well, and that not all of the weight gain is fat, but lots of good stuff like amniotic fluid, increased blood volume, these humongous G cups I'm rockin' these days, and of course BABY! I haven't forgotten that I gained an incredible 80 pounds with my son, but I'm trying to also remember that was a long time ago, I was young and thought I could eat whatever I wanted without penalty. This time I know better and am a lot more active at baseline to begin with- so hopefully I can avoid that situation again.