can denial of physical intimacy be a ground for separation

Yes, you can file the divorce petition against your wife relating to this ground but you have to submit strong evidence with the petition to the court. And you have to provide maintainance to your daughter if she is not ready to stay with you.

Yes it can be a ground for divorce. However , you should take this practically. Think about the future of your daughter and then move ahead with divorce on such ground. You may be asked to pay one third of your salary to wife and one fifth to your daughter for their maintenance. Also permanent alimony shall be quantified on basis of salary with perks plus the assets that you have less liability of dependent family members.

Yes , denying sex is the ground to get divorce and without sufficient cause denying sex there is no maintenance under section 125 of crpc.
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