If i remove one from eleven it becomes Ten and if i remove one from nine also becomes Ten.

Question

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?

Answer 1

In Roman number its possible IX X XI

Answer 2

In roman numbers 9 means - IX
and if I remove 1 then it becomes 10.