How much that strange confession explained to him! The painter’s absurd fits of jealousy, his wild devotion, his extravagant panegyrics, his curious reticences – he understood them all now, and he felt sorry. There seemed to him to be something tragic in a friendship so coloured by romance.

– Oscar Wilde

The Picture of Dorian Gray, Chapter 9. After Basil’s "strange confession" of love for him, it is clear that Dorian doesn’t not have the same romantic feelings for Basil. When he speaks of it being tragic for romance to intrude on friendship, this could be seen to be foreshadowing of how Basil will meet a tragic end at the hands of the man who idolizes.