S.
It is easier (although it may not seem so!!!) to set limits at 14 months, than at 14 -- although that seems a long time away, it comes very fast. So, it is best to let him know that you are his parent and that he will not be running the house. Consider taking a week, of what will probably be h---, to get your new standards into place. Then, stick by them.
I cannot tell you how many times my daughter has heard other children (10-14) saying, "yeah, my mother said she was going to that - but she always lets up - no big deal if I get in trouble for that..."
One of the best gifts you could give your child is the ability to independently fall asleep. Good sleep habits are essential to a healthy life. If you could find the book, Healthy Sleep Habits, Happy Child - I would strongly suggest you read it.
Both of my children nursed exclusively. My oldest one would later drink water from a bottle (at about 10 months) - my younger one went straight from nursing to a sippy cup, briefly - then to a regular cup (I guess she wanted to be like her big sister).
You may want to check with your pediatrician to be sure he is getting the nutrition he needs so that he is not hungry. He/She may have some suggestions to help you. Once you know that your son is fine and healthy, you may want to consider that dreadful week. Think of it as an investment in the future.
Your family is fortunate that you have decided to take control of this situation. Everyone, even your little son, will benefit from a positvie change.
Good luck,
S.