I know this very nice page: 
Chinese Family Tree | How To Decode It, How To Understand It (ltl-school.com)
Today is special for me: It’s the first time since February 2020 (…) that I am invited to dinner at my Chinese…? And that is my question. I always thought I can call her my 嫂子, but a Chinese online friend has just told me she is my 妯娌.
She is the wife of my husband’s older brother.
Of course, it is also a good language training to call her my
丈夫的哥哥的妻子。
So, please, can you tell me who invited me today? 