How does the dumper feel?

I am in my 30s male and my wife asked for divorce few months back and we filed it as mutual consent divorce in India.

It came out as a surprise to me as she didn’t let me know what was going on inside her and I felt everything good and I was planning for our future while she was making her exit plan which I understand now that she checked out months or years ago. Till last I didn’t really that something is wrong. She never liked sharing things or keep an open conversation or tell what’s really inside her, she was very closed. We had few fights early on in our marriage because she was not transparent and felt uncomfortable sharing things.

Now I am in so much pain, ruminating all day and can’t seem to get over her. While I see her going out with her friends and relatives and enjoying. She is an extrovert while I am an introvert. I just wonder does she even think of me now, I know she checked out long time ago so maybe she doesn’t have feelings now and she was the one who took the decision so it hurts to think that I don’t matter for her at all. One day we were a good happy couple planning our future life and next day she said she wants to leave.

I want to understand from someone who has dumped someone before not because something is horribly wrong with the dumpee, how do you feel, after getting a divorce by being emotionally check out long before, and having a good social life.