I read it in English as "Narcissus and Goldmund". The subject at the core of this book is very dear to me and it really moved me and like you, I was affected for a long time. I give away all the good books to friends saying "You must read this, it's excellent!" and thus I no longer have my copy. I must read it again.

By the way, if by some chance, there is a big overlap in our tastes, I recommend the fictional work called "Loving Vincent". It's a "moving painting" rather than a "movie".