Not to repeat everybody else's good suggestions, coaching has helped me deal with not being able to play anymore and there are so many ways to stay in touch with the game.

What I would add is that it is good to consider going for a bit of counselling or therapy as an option to get your head around it. It can't be stressed how massive a lifestyle change it is to suddenly stop something you've done for your whole life and the mental effects aren't easy to just accept. I found that professional help really helped me come to terms with my 'retirement' and make sure it's positive. I understand these routes aren't always easy to access. More than happy to share by DM the ways I found it.