Seasonal Depression

In the Winter I get depression because it's dark and gloomy I am a stay at home mom and it's quiet being home alone not much to do besides cook, clean, run around shopping quickly with the kids. I feel sleepy like laying down and resting I like to sleep in and recently I feel like what am I doing I'm treating myself like how I would treat a child with flu here sit in bed all day you can eat in bed have ice cream, jello etc. And it's not healthy staying in bed most the day. I also have Procrastination I don't know how to get rid of it? I wait until the last opportunity to do something and get behind. I feel lazy, lethargic, sloppy. How do I get up in the morning and get to doing my tasks?

A job opportunity presented itself but I feel guilty about it like I'm abandoning my kids to work I want to ask is it okay to go to work is it okay to leave kids with babysitter or grandparents I'm just like maybe next year when they are in school I can work those hours while they are in school. I'm so indecisive if I want this job. It's emotionally difficult to not be with your children and away working.

What is seasonal Depression

In the winter you know when it's freezing you're stuck indoors I get seasonal depression in the winter and I feel like closing the curtains because I don't want nosy neighbors looking at me throughout the day so the house gets darker and my doctor recommended I keep window curtains open and the treatment is to have bright lights installed.

Edit yes the doctor said I have low level of vitamin D wrote me a prescription and told me to take multivitamin I haven't taken it yet thank you what other supplements do you recommend?

Edit: I spoke to my Doctor and went to a psychologist and they both recommended the light therapy and being outdoors to get natural sunlight. There no prescription in this circumstance for seasonal depression they are the ones who prescribe and make recommendations for that there's also secondary side effects in certain medications. I'm looking for more holistic treatment or some advice what people do when there have been days they haven't felt much like doing anything and feeling gloomy