There is a spot right between the brain and the mouth. It is there for a purpose to "strain" things or "clean" things before they fall out of your mouth. Most people use this area quite successfully and as a result they are well liked and appreciated.

But there are others who, even though they know about that spot, chose to ignore it and let anything fall out of the mouth.

It is usually because they think that their opinion is so wonderful and valid - and will be the last word and sway everyone over to their side. For instance, the entire office should stand up and agree with her and shout at the woman YOU LOOK LIKE A DIKE!

Happily most of us have more common sense AND we are considerate enough of the other person's feelings that we either use that spot and "edit" or we say nothing.

This woman's opinion, even though irritating, is worth nothing.
Keeping that in mind, ignoring her would be the best approach.

If the girl who cut her hair likes it - that is all that matters.