I stopped pumping at work when dd was 12 months, and I was thrilled to stop lugging that thing on the train, shutting my door for 40 minutes a day, planning meetings around my pumping, etc. I still pumped at night because dd took a bottle of ebm before bed (I never made enough for her at night) and I wanted to keep up my supply. I think I gave up the night pumping around 15 months, when she was happily drinking soy milk and had given up the bedtime bottle.
She nursed 2x-3x a day until she was about 20 months, and started tapering off on her own after that. Around 21.5 months, she weaned completely. I don't think it had anything to do with the end of pumping -- and I missed nursing a million times more than I ever missed pumping. It's one of the things I look forward to most about the next child, whenever we have the next one -- the chance to nurse again. Pumping, I look at a little like diapers -- part of parenting, at least for me, but not something to particularly look forward to.
Just my two cents.

-Debi
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