Divorce case on mental cruelty grounds

Married in 2016. Wife B.Tech , working in Bangalore last 5 years , lived in her own rented houses , earned nearly 50k per month. Never came back home of husband. Husband ,B.Sc., working on contracts with companies, earning on contract basis. Last three years earning if monthly divided is 125k per month. Dependent Father,mother and grandmother. Father has pension of 20k, thus dependent on husband. All live in ancestral house at small town of UP. Wife filed case under section 24 of Hindu marriage at Bangalore. Wife written in petition that don't want kids and don't want to live at home of husband. Trying to say last lived home , her own pre-marriage rented house , as matrimonial home. Still can claim maintainence ? How hard is to prove mental cruelty ? Husband only visited her house in bangalore for 55 days in 3 parts in 3 years. Not lived together for last 2 years. How should husband defend allegation and maintainence/interim maintainence?