Nursing at 21 Months

Oh my goodness!  So last night's sleep was a little rough guys!  Railynn is 21 month & is still nursing.  Last night she woke up several times to nurse or comfort nurse I'm sure you could really call it!  I love breastfeeding and the bond it has created between Railynn and myself but I am getting a little exhausted to be honest!  I know all the added benefits of "extended nursing" as well as the benefits in letting her "self wean" but when will she self wean?! LOL Just curious on how long other moms have been nursing their babies & how did you get your little ones off the booby??  We've been going strong for 21 months, no formula, but this mumma is pretty tired & exhausted!!  Send me your tips friends!!