Prefab-How many days a week do you work 5 hour shifts? I feel like a 5 hour shift plus a workout and I bet you go shopping for groceries, fix dinner for your H everyday--well, that sounds like a full day. Do you workout everyday? Perhaps 4 days a week is enough for tougher workouts and then just walk like I do the other 3 days?
What kind of SSRI were you taking before? I take Bupropion and I notice that it has a good effect on my libido. I guess I am lucky in that I mostly feel energetic sleeping six hours nightly about 80 percent of the time while rarely napping. However, I cannot do as much physically as I used to. I am probably not a good comparison as far as physical activity due to my age (53) and my injury. Though concerning an SSRI, once you start, it can be tough to stop.
Also, I know how little sunshine you get in the winter where you are. Today is the first day of Spring! Whenever it is not raining there, I recommend that you get some sunshine. Sunshine does wonders for my mood. Coffee and chocolate can be helpful too! And maybe try the doctor again? I hope you feel better soon.