I agree with Anna, you are drinking a lot of fluid there!!!! A personal question here, what does your urine look like? Is it dark for most of the day or dark and then very light as the day progresses? Dark urine may mean you are not hydrating properly and is something you should seek medical advice for esp. in regards to diabetes. And another question: do you eat paleo?
It is really nice to drink hot water alone. The taste is really quite pleasant, but you may not be ready for that yet, so why not try adding a flavor, why not try ginseng root? A slice of fresh ginseng root can be boiled up or just popped into boiled water, which will certainly take the edge off the plain ol' water taste. Ginseng has many health benefits.
There are other Chinese herbs you can take esp. if you are experiencing fluctuations in blood glucose/diabetes and many can be boiled in water to give a pleasant tasting drink which can been taken during the day. I would advise seeing a Chinese herbalist to get a full test done, you will then be given the herbs from him/her.
If you are used to making up and drinking the mate, Chinese herbs may offer a kind of substitute to your 'tea ceremony' until you can graduate to plain hot/cold water.
If you really can't face any of the above stuff, it is OK to start with juice of you then top it up with water gradually - so start on the first day with regular juice and on the second day water it down until it tastes weaker and drink that, then continue to water it down until you have a very small amount of juice per water ratio. This is a technique I used on my children who couldn't bare the thought of drinking water one summer a while back, within a week they were on 100% water, no juice, no complaints.