I also breastfed both my children.
DD weaned herself at about 18 months. I was 3 months pregnant at the time and I often wonder if this had something to do with it.
With DS I was ready to wean him when he was about 21 months. He was down to 3 feeds by then so I withdrew 1 feed a month starting with the daytime feed. This was the easiest to start with due to the fact that he didn't always have it anyway. Then the night feed, and finally the early morning feed, this was his favourite one. It worked well for me doing it this way and I found as I withdrew one it seemed to make the following withdrawals petty much non eventful. Oh and when I started I discussed it with him and told him what I was doing and why.
As others have stated substitute with lots of cuddles, create a different ritual (particularly when associated with bedtime or the like) and introduce a *special* cup that DC might like to help you choose.
Hope this helps and good luck!
(And how many of those who breastfed longer than a year did it 'cause they looked into it and decided it sounded like it was good for the baby? Most of my aquantances haven't done the looking into it part, but most of my friends (a fairly smart group, on the whole) have, with the result that most of my friends keep going, but most of my aquantances are shocked I haven't weaned yet)
I'll be really honest here, yes I was aware of the benefits of breastfeeding from the word go but I also liked the closeness and convenience of it.
