I know that some folks don't count tea as water, but I do. Adding some peppermint leaves to the water doesn't remove any of the benefits of the water. So that's how I can easily drink a gallon a day.
Maybe you could add something to your water to make it easier.
I normally drink hot tea, but when I want something cold, I make ice cubes with fruit in them to add to my water. Citrus is always a go-to for me - little orange bits usually, though I also love pineapple, grapes and cherries. I can't even look at fruit filled ice cubes without feeling refreshed and wanting to taste them.
Fresh cucumber or ginger is also a nice addition. Dress it up a bit and it looks more appetizing, tastes better, and is healthy for your body. 1870 days ago