i’m not really sure why people are upset or confused that the doctor didn’t say ‘i love you’ to clara
he’s literally never said i love you to anyone in 52 years of the show
he doesn’t say ‘i love you’. he says ‘we had the best of times’, and ‘i’ve got a duty of care’, and ‘you were seared onto my hearts’, and ‘i shall miss them, silly old fusspots’, and ‘martha jones, you’re a star’, and ‘just go forward in all your beliefs, and prove to me that i am not mistaken in mine’
he doesn’t need to say ‘i love you’. his companions know.