To annoy or irritate someone especially by being near them all the time
I love Kate’s kids, but they are really noisy and messy. It’s been three days I’m trying to be nice to them but they are getting in my hair. I don’t know what to do anymore.
Cambridge Advanced Learner's Dictionary - 4th Edition
get in sb's hair informal
to annoy someone, usually by being present all the time:
My flatmate has been getting in my hair a bit recently.
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