Sounds all too familar here too! I feel I could sleep all day every day most of the time.... Like lightenup though, I would encourage you to go out for this celebration meal. It will almost certainly make you exhausted, but you feel like that anyway!! GO - enjoy yourself with your husband and you will probably have a really lovely time and its soemthing you can remeber on those days when everything seems so bad.
Also - the doctors stock answer - as my doctor and support workers has been, is that if you aren't keeping yourself busy then your body will naturally want to sleep.
I feel like I've been banging my head against a brick wall with that response - if I feel so drained, how am I meant to do anything in the first place?? At least if you really make the effort and go out with your husband (who by the sound of it is very supportive) then at least the doctor can see that despite all of this exhaustion, you are really trying to not let it destroy the important things in life.
I hope that makes sense and doesn't sound like I'm lecturing you! I have friends coming over for dinner tonight and am so tempted to call them and cancel BUT when we have the oppourtunity to do something for a few hours that might just take us out of ourselves I think we need to accept that yes - we probably will sleep all of the next day, and we can allow ourselves that because we've made a huge effort.
Happy Birthday and Anniversary - I hope what ever you do, you enjoy it :)