He indeed used to speak about him in the third person and would casually say "Alain Delon did this" (instead of "I did this"). He was widely mocked for it but he claimed it was a sign of "humility" (?!) because it was a way to avoid using "I" or "me"...

He became a huge international star in 1960 with Purple Noon, the first (of many) adaptations of Patricia Highsmith's The Talented Mr. Ripley. He was 25 and from that moment onward was recognized the world over as the sexiest and most handsome man alive. He continued to work with some of the most acclaimed European directors and starred in over 80 movies.

It's probably difficult to handle that level of fame and stardom if you're not prepared for it (or even if you are).