What's the best way to handle an interfering mother-in-law?

I've been married for seven months and I feel I am more married to my mother-in-law than my husband. She is relentless with her criticism and constantly questions everything I do. She doesn't live with my husband and I (she lives in the main building) but she has a key to our house and lets herself in all the time. Her attitude is beginning to affect my health. Help!

Linda says...people will treat you the way you let them treat you.

Please share your thoughts
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