I'm sorry that you're still struggling with enjoyment issues PB. Try a few runs without the Thief of Joy?
I've just finished Week 2 of Couch to 5k. 3.54km in 31 minutes.
Left knee a bit sort after the run, so I might give it a few more days before starting Week 3, which looks like a bit of a rest week anyway, only 28 minute runs instead of 31.
I'm using a "Get Active" Couch to 5k app on my phone, mostly because that's what I was using a few years ago last time I tried this. I wouldn't recommend it, sign up requires all sorts of data they really don't need for a running app (like your proper home address!) which I got around by having garbage data in there from last time I installed it and not updating it.
It's fairly simple, just give voices prompts of when to walk, when to run, works with the audio app I use to listen to things while I'm running. I log the runs in Wahoo fitness app, as Strava doesn't connect to sensors anymore I was insterested in HR data. Wahoo posts to Strava when I finish the run.
My Strava is
here if anybody wants to connect via that.