I found, that once you tell one of these people, quite without apology, to take their opinion and shove it up their ... , then the comments generally stop pretty quickly.
I have zero patience for this kind of crap, and TBH, I never understood why people pull out the "Oh, I am still BF because I don't want to wash bottles" or "It's cheaper" lines, when what they really want to say, "You know what? **** off, because you are clearly an ignorant fool"... So I pretty much say what I think - I don't do the passive, apologetic, meek stuff. DD2 is now almost 3, still breastfeeding, and the only people who ever comment now are those who don't know me well enough not to.
Congratulations on making it as far as you have, it is a great achievement! Hope you can continue as long as you wish to. :)