I am a 5 letter word.
You know me very well.
I am name of a girl.
If you remove first letter it becomes another name of a girl.
If you remove last two letters it also becomes another name of a girl.
If you remove my last 3 letters, it becomes inevitable when you are talking about yourself.
If you remove First 2 letters and last letter, It becomes a word which is used for indicating a thing.
First and last letters are same and used to indicate singular.
If you remove last letter it becomes name of a boy.
What am I?