Marital problems

I have a cousin who is in a marriage where him & his wife hardly speak to each other, they don't have an intimate relationship since they have a daughter who is 5 years old. She argues with him unnecessarily. Since the past 15 years he has been living like this. The reason being she didn’t want to come live with his mum after his father passed away. She told him I will make your life a hell. He has given her 2 talaqs but his mum tells him that he should not divorce her because the family will talk& him & his Mums biggest fear is that he won't ever see his little daughter again. He said that this marriage is just pain & hardship.

Mufti Saab in this situation what should he do?