Frequency: The word is one of the 700 most common words in English.
Note: 'My' is the first person singular possessive determiner.
1.
A speaker or writer uses ~ to indicate that something belongs or relates to himself or herself.
I invited him back to ~ flat for a coffee...
John’s ~ best friend...
DET
2.
In conversations or in letters, ~ is used in front of a word like ‘dear’ or ‘darling’ to show affection.
Yes, of course, ~ darling.
DET feelings
3.
My is used in phrases such as ‘My God’ and ‘My goodness’ to express surprise or shock. (SPOKEN)
My God, I’ve never seen you so nervous...
My goodness, Tim, you have changed!
DET feelings