Eating healthy with baby #2 on the way!

What did you do to maintain a healthy diet when you were pregnant or while your wife was pregnant? By no means am I "going on a diet" while pregnant, but I do want to try and maintain my same eating habits but am finding I am having to change the way I eat. Where I used to be content eating 3 times a day, that is not working for me now that I am pregnant. My stomach starts growling 2-3 hours after eating even though I have no appetite (nausea is wonderful). So I am having to take snacks everywhere I go to try and keep from having that 'hungry' feeling. But absolutely NOTHING sounds good 99% of the time so I haven't been making great choices when something finally does sound appetizing. What are some things that you have done to maintain a healthy diet AND exercise while pregnant? I haven't been working out for awhile due to the death of both of my parents last year. Now that I am pregnant I feel like this is the perfect time to slow into exercise again. Any tips on how to do this? I used to go to the gym but am not sure I will be able to do that for awhile. ALSO I am already overweight while pregnant. I was over 90lbs heavier the last time I was pregnant, and although I am not as healthy as I would LIKE to be this time around, I want to continue the positive changes through this pregnancy and not gain 40 lbs like I did with my last one. Has anyone else done this while being overweight and pregnant? What happened with your pregnancy? Did you end up not gaining as much, loosing, or was it like any other pregnancy? The book my doctor gave me said that the case of extremely overweight women it is actually ok for them to loose some weight while pregnant as long as the baby is growing and healthy and so is mom. Any help or advice is welcome!