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I have a colleague who has one year more experience than me and probably from other bigger companies. When she joined our team, I thought I would learn a thing or two from her. When I told her that she must point out to me if she sees I can do something in a better way or if she thought it needs improvement. She agreed.
There have been a lot of instances when she had easily the chance to come up to me in person and tell me where I could improve and she did not. Instead, she happily does it in front of other team members and in fact my seniors.
For example, when I ask her what she thinks is missing in it, she tells me "nothing" or "I just wanted the documents to be in one place" whereas she earlier spoke to my teammates or colleagues that "the documents need to be rewritten". There is a very big difference between having to rewrite a doc, and the need to keep them in one place. Obviously, her goal is not to correct or improve me, but to come up better than me in front of others.
How do I deal with this?