tldr; stopped forcing myself to read + cut social media habit + cheated
I used to be a voracious reader too, then clinical depression hit, followed by anxiety and my reading habit dropped. I'd still buy books intending to read them, and they'd just go unread. I'd see my increasing pile of interesting yet unread books grow larger and that'd stress me out more while making me feel like a failure. Which would just depress me even more. It was quite a cycle.
Therapy helped me realize some patterns..
I realized that whenever i tried to force/ guilt myself into doing anything, I just ended up resenting myself which sent me into a self-hating depressive cycle. So I gave myself permission to not read if I didn't feel like it. It removed all pressure, guilt, resentment, and any negative emotion I had towards myself for not doing something that I thought I should be doing. Which also boosted my mental health.
I realized that my social media habit interfered with my reading as it lowered my attention span. Plus seeing the world going to hell in a handbasket worsens my anxiety and depression. So I broke that habit. The only way I could do it was by forcing myself to go offline. Took a few tries to get it right but I realized that I naturally gravitated to books when I didn't have social media to go to. I now have monthly SM detoxes where I avoid SM for an entire week, which has also helped my mental health.
One other pattern I recognised was any stressful event in a book (even fictional) would stress me out and make me too anxious to read anything, which is a bummer since I love murder mysteries and non-fiction. I also realized that when I knew how the book ended, I could it read it with negligible anxiety. So that's what I do, even though it feels like I'm cheating. I read the first few pages and when/ if I start stressing out, I read the last chapter, put the book down and go for a walk/ do some outdoor activity. Invariably I end up grabbing the book and reading it cover to cover while enjoying it, which imho is the most important part.
A good friend restored his reading habit by making his exercise & diet cheat day as his book day. By associating pleasure (via lazing, chocolates, & whisky) with books, he rediscovered his joy of reading.
Go with whatever works for you.