I hate being pregnant in the winter

I'm pretty sure I have seasonal affective disorder. I get down by January/February every year. This year though I'm also pregnant and due at the end of February. The combo is killing me. I already am feeling down and cooped up from the season. And now I'm third trimester pregnant and I just have zero energy/will to do anything. I have a two year old and I love her so much but I literally have no energy to do anything with her and I feel horrible. My husband keeps just staring at me asking what's wrong, and I'm like nothing's objectively wrong I'm just miserable! He has severe (but well managed) depression too so he knows exactly what it's like but he insists I'm fine and just need to rest, even though resting just makes me feel worse. I don't remember feeling like this way at all with my first pregnancy, but that baby was born in September so I know it's just the winter. I know I will feel so much better in a couple months, but dang this sucks right now.