In your situation this is I would try to do... Definitely eat a little something before going out
Maybe eat half your supper and the other half when you come back from your walk... OR have a snack of cottage cheese mixed with strawberries, this is very light and won't weight you down, you don't need a lot just half a cup of each... OR you AND hubby have a snack and BOTH good out for a walk... I'm sure a walk won't do him any harm either no matter how slim someone is they can always use a good brisk walk
... Eating half your planned supper is probably a good idea because when you come back from your walk you may not be that hungry to finish it off, especially if you drink a nice large glass of water as soon as you walk in the door after your walk...
About eating before bed... I personally don't think it makes that much difference if you eat late or early, if it's all counted into your calories for the day.... Because dieting is all about calories in vs. calories out, I think... I wouldn't eat a huge meal at 10PM, because I'd never be able to sleep, but 7ish, is fine ...
Oh, and just another 2 cents of mine if you don't mind
... If you're tired after a meal it may be because there are too many processed carbs in your meal... You should try to avoid processed carbs, like white or even whole wheat bread, white rice, white potatoe, anything with sugar in it too...
Hope this helps and keep us posted on your progress