Answered by: Maulana Imran Mughal
I tried saying to my wife once that I wish to divorce her by explicitly saying “I am giving you a divorce” but she ran out of the room and started shouting and fighting with my family. She has since left the house and gone to her cousin’s house and has blocked me on WhatsApp and does not answer my calls. She becomes violent when I mention this matter to her. I have since written her a letter, saying explicitly that I agree to give her a divorce / talaaq and did this in front of two male muslim witnesses.
I am unsure if this was valid because I know I should say it to her verbally but she refuses to sit down or listen. But I have said it multiple times to everyone that I have divorced her / given her talaaq.
We have not had a sexual relationship for quite some time over a three-month period now due to ongoing conflict and the constant abuse and disrespect she shows to my mum.
Please clarify what I should do if anything as I have not changed my mind and did not make this decision in anger.
The divorce will be valid and the marriage has ended. A divorce will still be valid whether she hears it or not, or whether she agrees to it or not, whether stated in front of her or written. 
Only Allah SWT knows best
Written by Maulana Imran Mughal
Checked and approved by Mufti Mohammed Tosir Miah
Darul Ifta Birmingham
 Ibn Abidin, Raddul Muhtaar, (4:455).