The inheritance is decided in accordance with personal laws applicable to the owner.
It is beleived that you are Hindu.
If yes, your spouse, children, mother are ClassI legal heirs and shall have first right.
However during your life time they have no forced share in your self acquired/earned estate and you can dispose it in any manner as it pleases to you e.g. WILL/gift/sale etc.............
You may download the proof of having been staying separate a few days back only.
So that you can establish that you have gifted the property to your mother much before staying separately.
While deciding mainatainance/alimony the court shall consider your estate/income.
Rest your able counsel can guide you further.