Click Fast Travel, select Myrist Library, and you will also be given the opportunity to travel to The Blinding. Seems like The Blinding should be available from a link at the top of the map where the pic of Luclin appears.
I discovered that 2 days ago. Before, I used my pocket spires to EW then the spires there (which is a hassle on Test with the problem of zones not being open). I wanted to go to Myrist, wasn't in my home and used fast travel... and saw the Blinding. Please, fix the map!
If you're already in BoL it sometimes shows The Blinding at the top of the map. or it might be when you're already in Myrist.