What's normal? The WHO say that babies should be BF for a whole year, and the lucky baby gets nursed for 2 full years. In Africa, I have heard the norm is 3-4 yrs, in Biblical times, it was 4-5. If you compare us with the apes, it comes to around 5yrs, IF we were apes. Babies who have allergies, need longer time at the breast to keep nourished, since their choices are limited, and BF builds immunities.
Wait, you asked about if anyone has BF longer than "normal". I breastfed my first for 2.5yrs, as I planned on 6 mos, and then went to child wean. I weaned him at 2.5yrs, as another baby was on the way. BF her for 11 mos, because she went into formula for failure to thrive. The next weaned at 10 mos, to the bottle on her own. The next one nursed a full 2 yrs with her brother, who went on to nurse 18 mos, and as I really can't tandem nurse, I weaned him at that point. The next girl also was weaned by Mom at 18 mos with another baby on the way, and he is currently coming on 6 mos. The time I planned to go with my first.
I don't believe too much in making a baby cry, unless it is paramount for whatever reason. So, I try to encourage weaning because I HAVE to for health reasons. Daddy will rock them to sleep, and eventually they will come and sit next to me at night to fall asleep while I am nursing the other one. It only takes a couple nights, usually. I can't imagine force weaning a baby baby, because they just can't be reasoned with. But, if you have to, I am sure there will be lots of advice about it on here. But, just don't do the CIO method. That is heartbreaking for baby AND mom. They need something for comfort, let it be you, or a substitute. JMHO