Why so dark?

I have been quite confused recently. While granma and grandad were staying I had got used to sleeping in a bit in the mornings, so I knew it wold be a shock when I had to start getting up early to go for a walk before mum went to work. However, the first day after she got back from holiday she got me up in the middle of the night to go for a walk! It was only just light when she went to work. She came home for lunch as usual, but by the time she got home at the end of the day it was nighttime again! I didn't understand this at all. Mum says it's because it's winter and the nights are longer than the days, but that doesn't make any sense to me. It's also get really cold and rainy and I don't like going out in the rain - I don't think I like winter very much. Mum says it only lasts for 6 or 7 months - that's as many months as I've been alive, so like forever!!!