A.G.
Whenever you try and deny a child who is unwilling to wean, you are going to encounter problems. If you let him self wean when ready, or even just nurse at night until he is ready to quit, you will have a lot less heartache and a better adjusted child in the end.
Just as an aside, 5 1/2 months is really early to be weaning. You might want to look at what the research indicates before you decide to quit completely. Here's a few links that might help you.
http://www.kathydettwyler.org/detwean.html
http://www.naturalchild.com/guest/norma_jane_bumgarner2.html
From the American Academy of Pediatrics - http://www.aap.org/advocacy/releases/feb05breastfeeding.htm
"The policy recommendations include: Exclusive breastfeeding for approximately the first six months and support for breastfeeding for the first year and beyond as long as mutually desired by mother and child."
From the World Health Organization - http://www.who.int/child-adolescent-health/New_Publicatio...
"Breastfeeding is an unequalled way of providing ideal food for the healthy growth and development of infants; it is also an integral part of the reproductive process with important implications for the health of mothers. As a global public health recommendation, infants should be exclusively breastfed for the first six months of life to achieve optimal growth, development and health. Thereafter, to meet their evolving nutritional requirements, infants should receive nutritionally adequate and safe complementary foods while breastfeeding continues for up to two years of age or beyond. Exclusive breastfeeding from birth is possible except for a few medical conditions, and unrestricted exclusive breastfeeding results in ample milk production."
It's always a good idea to see what the experts recommend. :)